Blimey I'm definitely in the hard sell zone.If only. I think I have talked myself into it.
As the bike is only used for getting from the swim to the run (and I must always have a helmet) I have not seen the need for a cap, but I guess there will be some long rides if I ever get round to an Ironman.
TBH I doubt the caps will be worn under a helmet, in anger, on anything other than chilly mornings.
But as a fashion accessory, and post ride statement it's a must.