Piston size and oil thickness

[Dworski]

I was wondering if anyone could enlighten me on this subject.
Wouldn`t putting in pistons with larger holes have the same effect as changing the shockoil to a lighter oil?
And: I notice that some are drilling extra holes in the pistons. Wouldn`t they achive the same effect just by putting in pistons with larger holes?

My last question is: I`m running on a indoor clay track with a bumpy straigth and some big jumps. On the straigth I want the car to go smooth over the bumps(obviousely) and on the jumps I want the car to land smooth and not rebound to quick. Are those to things even possible to achive at the same time?
:-)
So far I have just tried it with 27,5 wt front and back with red springs front and yellow rear. (mid motor car that is) 55 piston front and 54 rear. The car is ok on the long straight but rebounds to quick on harder landings resulting in lost control for a split second.

thanks,
Jon