yes I use thumb under technique on the lute, this puts the fingers at a better angle for contacting the pairs of strings on each course. I use regular classical guitar technique on the guitar but if I've been playing a lot of lute it sometimes takes a while to get back into "thumb out". On extended scale runs I use pi, but where there is a mixture of scales and bass notes then I mix p,i & m as needed. I don't use nails which makes classical guitar more difficult.
Glad you enjoyed the video by the way,