Symmetrical Spinnakers

Except in the matter of ease of use  (and faster launch speed for really big ones), is anyone claiming that asymetrics are in any way "better" than symetrics?  In what way?

Can an asymetric run a bit higher (and hence faster) due to the tighter luff?  Is the shape somehow more efficient?

I note that big yachts always (appear to) have symetric kites - but that could be because they rarely sail faster than wind speed (but then, nor do some modern asymetric dinghies)

Many racing yachts will carry both, to suit the conditions, provided class rules allow. Infact, wasn't there, in the old days, a sail called a "cruising chute" or something, which was asymmetric?

J-boats, yes indeed, but as it says in their brochure:

"Theirs is the so-called racer/cruiser category: boats that perform well enough to race but which are comfortable and easy enough for the family to daysail and cruise"

Also cruising shutes, I'm familiar with, but always thought they were for flotilla sailors (like me!) who can't be trusted with a "real" spinnaker.

I was thinking more of Americas cup giants where launch difficulty isn't an issue but raw performance is.  Any of those have asymetrics?

But set off a mast mounted movable pole or a fixed / slightly-movable bowsprit? 

This one is flown from a spinnaker pole, so it looks like a dinghy symetric & the sail looks pretty symetrical too.  BUT in the 2nd photo, the kite is inside out, indicating that it is at least gybed like an asymetric!   IE they reversed the kite during a gybe, reattaching the pole to the same corner of the sail?  Best of both worlds?

Here's a decent summary:

http://saltashsc.proboards18.com/index.cgi?board=lessondb&am p;am p;action=display&thread=1122591041

forgive my ignorance, but I'm fascinated.

I believe the IACCs have to disconnect the forestay in order to gybe. Ooh er.

"Theirs is the so-called racer/cruiser category: boats that perform well enough to race but which are comfortable and easy enough for the family to daysail and cruise"

That's the boat-show cushion syndrome. "Yes dear, of course it isn't just for me to race with my beer-drinking buddies. Look at those comfy cushions, it's a perfect cruiser too." The smaller J's are definitely raceboats.