Spank that cute little bottom

The point of WHF Op45. No. 2 is to teach the violinist how to lightly spank a cute little bottom with a soft circular wrist action.

How the heck (once again the mystery of sevcik op1, no1) to play Kayser no.4 without some form of left hand tension. Starting to play around with shifting and finger that might help although feels like extra work. Will see.

E.g. for a stretch between 2nd and 4th, simply shift up a semiton and use a 1st finger instead of the 2nd and keep the 4th finger as before. and then shift back. perhaps shifting is easier and faster than stretching a finger.