Hi,
IMO/IME stripping the lower nodes of leaves gives the following benefits:
1. Leaves will not rot under the substrate. Leaks nh4 and will help clog the filter.
2. Light will penetrate easier to the inside of the plants. This results in thicker bushier growth.
3. With the lower stems bare it is easier to plant stems SINGLY and allow better spacing.
4. The longer bare stem can be pushed deeper in the substrate. They soon will get taller
Drawbacks are more planting work (a little and so what?) and time but it will be worth the effort. If we are doing the right things the plants will soon fill out and grow, no?
Planting several stems together is 'easier' and looks nice initially, but trimming the plants as they grow in will give the same effect and also allow you to control this growth. Observation is easier as you have seen it grow.......
The plants will be healthier and look better and should have a whorl of leaves close to the substrate as it grows. If this does not occur, then they are too close together or too thick and need trimmng..
You can always loosen the substrate first with your finger to help.
Remember too that stems are bouyant and want to float. The taller/more leaves, the harder to keep in place initially. Less height/leaves will help this at first.
Hope this helps.