The climbing in Yosemite has so far been crack-heaven. "Thin fingers" to "flared Chimney" and every width in between. Learning the necessary techniques has so far been an on-the-job affair, and mandatory training at that. Our first Yosemite "offwidth" was about 30cm wide, 30 metres into the pitch and several metres out from the last good protection! Sustained fist jamming was consolidated on the very same pitch. (Sacherer Crack 10a, El Cap Base). Our chimneying has been learnt on the flared featureless chimney of pitch 6 of East Butress on Middle Cathedral Peak, (below). The Americans have several descriptions for the techniques required - arm barring, leg bar, back and footing and a few more. However, I find our British word "thrutch" describes the whole range rather nicely and more realistically.
One thing they've definitely got right over here is "taping-up". (The practice of covering the back of the hands with climbing tape to protect the skin whilst crack climbing). My initial scoffs have turned to a very real interest into how to make these "tape-gloves", after increasingly trashed skin on my hands. S