well i track stand most of the time. depending on the amount of space and time i can usually hold for the duration of most lights - say 2 minutes or so with maybe a little forward roll - if i'm WITHOUT my panniers and stuff (i.e. on a rec ride) i can stand longer b/c i can also hop and get back to the right spot if i drift a little - harder to do with the panniers and backpack for commuting b/c of the uneven weight.

i clip and unclip left foot first unless there's some reason to otherwise (like a long light and a curb or rail to rest my right foot on)

also when racing i clip in last with the left foot. and when i cycle-cross mount/dismount i do it on the left side, so left foot last to clip in, last to unclip.

i've really been working on my track-standing the last year and can go about 3 times longer than about 1 year ago. with practice it's not so hard - although fat MTB tires make it easier.

don't really know why left-last... but the chainstay is one of the reasons... i also always mount the bike from the left. i have tried right-side mounting and i can do it but it just feel odd.