i've asked this question before and was told it was ok. if you've been manipulating the stem while they've been growing i am sure all will be fine with doing both at the same time. another thing to take into account before you attempt to lst is the available liquid in the main stem. i wouldn't attempt to bend or lst anything if you just watered or a lot of water is still in the stem.
if you're plan to clone the top, water 1st, wait 30 mins to take your clone, and give it a couple of days to let the soil dry out to start lsting. hope that helps.