He does use pots 2:38
Not in the video I posted.
Well, the having less DPS than Lanns does seem to be true. I notice that sword Lanns use so little stamina that they never really have to stop attacking, and just spam slipdash for every move while Vella seems to use a decent amount of stamina for her skills (which also seem to have longer invincibility frames?). Sword Lann does look somewhat less flashy, but in the end, you're spamming the same skills over and over. I can't really say for sure, but it looks like it's easier to avoid attacks as Vella than a sword Lann.
Lutiy used stamina potions.