Back to the OP: To maximize my climbing speed, I keep my butt in the saddle as much as possible. On a long climb, I'll stand for maybe 1 minute every 15 to change my muscle firing pattern briefly. Although as the climb goes on and on for over an hour and I get tired, I stop standing because my legs just won't allow it anymore. For sure, standing is less efficient for me. If standing is your thing, just standing on the trainer, varying cadence and resistance to simulate various climbing conditions. And of course strength training twice a week however you climb, working every muscle that's ever gotten tired on a bike ride.
In winter, on my rollers, I do a pedaling drill once a week, otherwise just the normal stuff: a good bit of Z2 steady state and the usual intervals. I didn't ride one winter and the result was so pitiful that I never did that again. I do "start over" in the fall. I take September off the bike and hike instead. Then I start back with mostly steady state on the rollers and cross training like fast walking and running. And of course I go to the gym starting with general strength training and progressing toward cycling specific training in May. I gradually add Z3 intervals, then a little Z5, then longer Z4 and eventually the hard stuff, but by then it's spring. In April (I think that's spring) I do low cadence climbing intervals once a week. My main goal, all the time, is don't get injured. That's the reason for stuff that doesn't seem directly climbing related. I never have been.
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