I think it might be the strong clutch spring and a lever span made for manly German hands that means the clutch bites at almost full extension of my fingers. Luckily it's span adjustable and by filing down the adjuster cam I now have much better control.
But, I noticed my right middle finger felt it also wanted to curl over.
I wonder if it's a product of high bars - 50mm risers added by PO, (I think these put my wrists above my elbow height, perhaps affecting circulation to an extent?) and the special bmw grip shape. But I've never experienced this before despite having many BMWs with these grips, and don't feel it on the C72 so don't think I'm losing my strength.
I'm going to try the new lever position before removing the risers but, as I'm very lanky, I wondered if any more normal sized riders had also experienced this. I'd have thought so but have never heard of it before.