Shimano "dealer" (assembly and adjustments) manuals are on-line, and very useful if you want to do any adjustments yourself. I have this pdf: DM-UL0001-02-ENG.pdf, from http://si.shimano.com/

From the front derailleur pdf, UM-5ND0B-001-00-ENG.pdf:
When the shifting switch is operated, the motor which drives the front derailleur will operate to the shifting position without stopping, so be careful not to get your fingers caught.

Yeah, the front derailleur has a powerful motor. I've accidentally shifted without turning the cranks (then shifted back), and nothing was damaged.

To get to the smallest sprocket when I'm off the bike, I sometimes shift the rear derailleur a few clicks, then lift the rear wheel and turn the crank to move the chain over.

Battery
I recharge quite soon after the battery indicator goes to blinking green. That's below 50% charge. (I ran low of charge on a ride, so the front stopped shifting, and I wasn't sure how many more rear shifts I had left. So I don't let it get that low anymore, and there's no reason to discharge a lithium battery that far anyway.)

I shift "all the time", often for just a few pedal strokes, then shift again. I used to get 600-1000 miles per charge, depending on how rolling the rides were. Rolling hills, with constant shifting, are where the Di2 is really helpful.

Now the battery is a little over 4 years old, and I have to check it often. It goes to blinking green after about 400 miles now, and will go to solid red, that's "low to 25% charge" within a couple of rides after that. So the battery is nearing the end of it's useful life. I'll wait until spring and replace it. It's been about 15,000 miles.