At the flying field today my friend aligned the prop on his BME 50 with top dead center. He said he read it on the Net.

I told him about this thread and that he might need to try several positions?

He was satisfied that it ran better aligned vertical with TDC.

Looked like the same amount of vibration to me? Hard to say without an instrument to measure the intensity?

He's happy with the way it runs and he was still able to prop it.

Ihad a ZDZ40 that was shaking the crap out of my H9 Cap (rhyme unintentional). Posted a question about prop alignment here on RCU. I tried every prop, every alignment, every swear word Iknew, and sent it back to Czech Rep for a look-over. Only thing that helped was switching planes. Weird.

The instructions that came with my Irvine 150 say "Fit the propeller securely at the "twenty minutes to two" position when viewed from the front of the engine."

Any external balancing of an imbalanced crankshaft will introduce lateral imbalance and should be avoided.
i.e it only adds to the problem.