sub 30 is definitely not possible for every human being, but sub 30 should not be hard for most of us.
If you keep practicing, as has been said before, you can achieve it. Personally, I found racing other cubers that were faster than me but not by much to be the best way to practice. I pushed...
I am not really sure if I prefer one hand
I use them for different things
I use mainly left hand for first block
mainly right for 2nd block
I use alot of mirrors, so depends on case, about even I would guess for CmLL
I use left for U and right for M in LSE
I use my right and left ring fingers for M and M'
flick on B side of DB edge for M'
flick from D side of DB edge for M
I only use left ring finger for block building
M2 I use right hand ring then middle
U and U' are index fingers
U2 is index -> middle on either hand
for LSE I only use left...
I find it interesting, trying to move towards colour neutral
I use roux, and I always do the orange/white on DL block, now I am just trying to do other blocks with white still on the bottom, I used to do fridrich with white cross, but still, I find even this quite hard
if I get used to all...
for a rubik's cube to be solved by a robot, it needs to find locations of colours, then it just applies algorithms that are coded in
for a cupboard to be opened by a robot, it needs to find locations of a handle, then it just applies stuff that is coded in
hmm... I think they are similar
just as a note, for all my EPLLs, I used M, U gen algs
when I switched to roux, if, after orientation, DF and DB are solved, I noticed I ended up doing the EPLLs
for example, Uccw, while doing LSE, I did M2 to bring one of UL/UR to the D layer, U' M U2 M' solves UL/UR, then M slice edges is U'...