Twos a crowd?

I'm presently on my third attempt at a wardrobe crop- my first 2 attempts (Nirvana Top44 & KC Brains' White) resulted in either males or mutants, so this time I'm trying Green Houses' "The Church". Bought 5 fem seeds for £11, and so far it's 2 out of 2 for females, so I'm well chuffed.

Anyway, I'm presently nearly 3 weeks into 12/12 and I've got a problem! Throughout growth I've attempted to keep the 2 plants separate ie no leaves touching either the walls or each other, and up until flowering that seemed to work out pretty well. Apart from having to remove a few of the big lower leaves I was able to let them grow naturally. However, since going on to 12/12 they seem to have hit a continuous growth spurt; they have both put out loads of lower branches and it's now reached the point where they're really pushed for space and are crowding each other (to my mind) quite excessively.

I know from previous posts that pruning during 12/12 is considered a no-no but am I better off resorting to "slash and burn" or should I just leave them to it? There again I've seen big, obviously mature plants that have had so much lower greenery removed that they resemble palm trees, so I'm well confused! BTW, before anyone mentions it, I've already noticed the height problem and am in the process of mylaring a new wardrobe that will give me another vertical foot, tho' sadly the floor space will remain the same. I've attached a .jpeg to try and illustrate my quandary.
Thanks for looking.

Have you considered using extreme bondage on your plants as a way to control their grow without cutting much back? You Don't have to LST, but you can move parts of your plant away from the other one, and use zip ties, or whatever else you prefer to keep some of the branches "out of the way".