If one doesn't want to worry about tangled roots, one cutting per jar/bottle will fix that. I always intend to separate them more after I get them in the house, but usually don't (for the ones that got grouped when I cut them.) One could plant the whole clump w/o separation, and/or take more cuttings. Compared to last winter, I have about 80% fewer cuttings this time. A lot of that is due to a freak late frost about 2 weeks after I planted most of last years' cuttings in the yard this spring. I spent most of this years' garden money on tiny succulents for mini gardening & postage for trading.
Time for some progress pics, good idea. Here's the good the bad, the ugly at my house. A few stragglers here'n'there not pictured, but this is most of them.
Some leaves are not happy on the left, that's normal. At that end of the row, the light is a lot less. Trying some rex Begonia vine this way this winter (Cissus discolor.)
Up on a high shelf I was worried wouldn't be enough light, so far so good.
I didn't notice in person but looking at the pic I see the water in that middle jar should be changed. A leaf has fallen in there & is rotting. If not cleaned/changed, the water will turn rancid enough to kill the 'plant.' A good comparison though, you can see the water should stay clear unless something like that happens. The others look fine (and brown bottles make it hard to tell, wish more beer came in clear, but I don't drink it at all & beggars a few nights before frost can't be choosers. A more fastidious person would change them as something else becomes available. I'll probably ignore it & just see what happens, I know how I am.)