I always took this to mean that a gentleman is a fellow who has at his disposal a wide range of skills and abilities, but also has the discretion and modesty to keep quiet about them until they're needed. If you ask me this takes fun out of being able to do stuff in the first place.
Of course, showing off isn't the mark of a gentleman. It's the mark of a cad. A bounder. A downright rotter. No prizes for guessing which side of that divide I'm aiming for, though, eh?
Anyway, thinking about it last night, it struck me that a cad does not have skills; he has 'social accomplishments'. By social accomplishments, I mean those little abilities which are of no actual value whatsoever except just looking pretty cool when you do them. You know, things like raising one eyebrow in a quizzical manner. As far as I'm concerned, half the point of privately working hard to be able to do things is so you can do them in public in an offhand, casual way and then look mildy surprised and a bit disappointed when other people can't do them: so being able to play the bagpipes and then not doing so just doesn't count.
Off the top of my head, a cad should be able to:
• Raise one eyebrow.
• Mix (or order) a martini without suggesting that doing so makes him James Bond.
• Perform a perfect riffle shuffle of a deck of cards.
• Blow a smoke-ring.
• Whistle for a taxi with 2 fingers in your mouth.
• Tie a proper bow tie, simply to make everyone wearing a pre-tied elasticated one look uncomfortable when you untie it after dinner.
• Undo a bra with one hand.
• Strike a match with a thumbnail, or light a zippo with one flick.
What else should a cad be able to do?