Me? Yea, I put them on my Brompton's M bar, [shorter grip-shift version]
the single bolt lets me loosen them and twist the long bar ends 1 up, 1 down,
when I fold down the bars.
were I to get the shorter GC2 i would not have to change them at all.

Longer rides the most comfortable 'grip' is open palm.. then the way the GC3
bar end J bend comes around, is where I place my fingertips..