forsaken and boaster

Some pros play both left and right prescriptive
for example forsaken, and hes insane at either i would say he plays left pres just to nerf him self a little
and on the other hand we have boaster ,he plays mostly left and gets shit on , then plays right and has some decent performance (also rare event)
i would say boaster should only play right pres.

what is left pres

Boaster should retire and free up the spot for someone that actually wants to win

tf is a left and right perspective