In my view it’s current py is a fair  representation of its speed against other boats you would find at a average club . 

Looking back I do remember that the system seemed to favour faster boats at most venues. This might have been due to the number of returns made and by what clubs. Extra laps also often give an advantage to faster boats in an average lap race (We can all remember the races where the wind died and we got stranded but the normal ones far outnumber these!).

The current system I think seems pretty good, but some clubs might need to be more prepared to apply tweaks to certain types of boat to fair things up, namely faster three sail boats on smaller waters.

If the sample size was big enough that would average out but most classes only return a few hundred races in a year, only 8 of 67 classes with a full PN returned more than 3000 races and only 2 (Solo and Laser 1) achieved 5 figure stats. With numbers in the low hundreds a single enthusiastic crew sailing most weekends will have a significant impact on the returns.

Possible exceptions being estuary/river clubs that may sail on a specific state of tide.

It's not unreasonable to expect tides to pretty much even out over the course of a year (You won't always be beating into it and a slower boat might gain a benefit vs a spinnaker boat downwind if they can stay out of it and the spinnaker boat can't. That said I *do* agree that the tide mostly penalises slower boats) , or to expect the club (I think HISC did, how successful/popular it was I dont know.) put a tidal adjustment on their own results. This is easier with a large club fleet and decent data, a small club with 10 or less boats all of different classes racing is going to struggle. You also need a handicap officer with the skin of a rhinoceros.

Another observation of mine is the bigger the PY gap and the longer the legs of the course the harder it is to sail a slow boat to handicap relative to the faster one. On short legs/small lakes the reverse applies. I think once you go above about 125 PY points gap in nearly all cases it's very hard to sail to that handicap gap in an individual race and at most clubs it benefits one side more than the other most of the time. Thats why I've come the conclusion that if you cant have class racing you should at least do fast/slow if by any means possible as sailing a Topper vs a Solo is tolerable but vs an RS400 its almost meaningless.

I belong to an inland club.. We're 19miles inland by river.... But yes the tide has a huge effect, we can get an incoming tide of a couple of MPH, and at the moment due to the low rainfall the incoming tide is having more of an effect than normal..

As the sailor of the slowest boat in the fleet on handicap, it's noticeable while I can generally keep within a close range of the others going down tide, Soon as we turn up tide,, the rest disappear leaving me behind.. 

Im not sure the point you're making here but from what i've seen and experienced the Great Lakes numbers only kind of work to a point in a very large fleet sailing a smallish course with a lot of dirty wind. Which is pretty much what they were intended to do.

At any other time they disproportionately favour the less well sailed slow classes, and I think this is because the sample size is reduced. It's a trade off - you only use the returns relevant to these events, but if only bronze fleet (for example) Miracle sailors turn up the national champion will walk the series the following year.

Works on the broads in some places where you can balance the water pressure off your bow against a hard quay heading, while you are sailing along 6 inches from the heading at a strange angle..

until...

You pass a dyke, then if you're not quick you go piling into the other side of the dyke..

In a cadet you had to go much further up the river before you dared to try to make it across. So you were not just slower but had to sail further. Also, if a 505 misjudged the crossing they could tack and sail against the tide in the channel. If I did that in a cadet I would never make it.

I agree with the idea that slower boats are disproportionately adversely affected by the tide.

At my current club we sail some series on PY, some where a correction factor is applied to account for tide and one with personal handicaps.

So what became of the Hayling/Chichester Harbour system? I remember talking to someone around a year after they brought it in and the comment then was that the Solo fleet had done exceedingly well. What I dont know is if they tried to develop it further or scrapped it. I think they did it before the large scale changes to the PY system that came in 6-7 years ago, and this might have led to a reversion to type - all clubs that did do adjustments that I know of (small sample, 3) all reverted because they were all leaning towards lowering the number of fast boats and the "new" system was in line with their findings.

So what do you want? Wind indexed numbers for classes with very binary performance like the 420 could be a thing but relies upon accurate recording of the wind conditions by someone and a decent sample size across all conditions. There is no point in going for wind indexing if you make it less accurate than a single number!

I don't see tide indexing ever being anything other than a local adjustment because there are far too many variables and whilst I agree that on the whole the slow classes take the biggest hit an average of by how much is going to be quite difficult to compute and again if its no more accurate than the standard number why spend hours and hours working it out? 

Someone asked how many coastal clubs make returns - that data is available on the PY list on the RYA website.

On top of that there are boats that are very suited to beat and running (Solo, N12) others that revel in marginal planing conditions (Laser), assymetric classes (200,400) that will fail to perform if there are no reaches, classes that excel in heavy weather (420, Fireball).

A whole range of skill sets who might be attracted to one class vs. another, back in the day the bandit classes were boats that had optimising potential but largely sailed by less skilled.

And on top of that many of the front end of the "hot" fleets don't get involved in handicap racing except for Great Lakes.

So maybe the system is remarkably good in getting the cream to usually get to the top, and maybe occasionally throwing out some crumbs to others.

Best thing is not to take it too seriously ... and don't pay too much attention to  the 4th digit of the PY number, it implies a greater sensitivity than is possible. 

The Americans had their D-PN system, which they are dropping to be replaced by RYA -PN

In larger boats they use PHRF which has many different versions around the USA, some versions take account of tides / wind strengths, as well as them all using boat statistics.. I see pages of complaints about it....

There is no perfect system.. you can't put monitoring systems on every boat (yet) and on every point of the river / sea / lake,  for wind  /tide / sun / someone sneezing. Without that no system will ever be perfect

The only reliable measure of my actual ability is when I go to Europe class events, I'm slow - but that's ok as it gives me something to work on. Europe.... fabulous boat by the way.

You answered the second part of your question on page one when you said 

Originally posted by A2Z  I think the main reason is that PY is a relative rather than absolute scheme, and therefore 1100 in one year does not need to bear any relation to 1100 in another year.

IIRC, when I started racing in 1965 the Firefly was the scratch boat, rated at 100. But I don't know if the PY committee maintained it as a basemark or allowed it to drift as is the case today (a look at the PN lists from the start until, say, 1970 would give the answer). Either method gives rise to anomalies as even the strictest one designs, (like the Firefly and Enterprise back in the '60s and the L@ser and many other SMODs more recently) develop and. presumably, get quicker in real terms.

The original Portsmouth Yardstick system did have a scratch boat set at 100, it was developed in 1947 by Stanley Milledge, who was in charge of handicapping racing at the Langstone Sailing Club and he designated the Island One Design as the scratch boat. I don't know if the Firefly's 100 PN was coincidence or planned.

FWIW, in 1961, the Firefly had a PY of 103 with cotton sails or 100 with Terylene sails.

103/98 for an Enterprise.

By the mid 70s, PY had been changed so an Enterprise was 118.

In the early 60s, there were a small number of  'primary yardsticks' which clubs were not encouraged to change, and lots of secondary yardsticks. Most of the primary yardsticks were very close to 100.

This approach might have avoided the @@@ Island Effect, where a club lowers all its fast fleet numbers and raises all its slow fleet numbers so Mirrors can race against Fireballs once a year, then returns a lot of Fast Fleet races where the numbers are all in Fahrenheit to everyone else's Celsius so to speak.