Before the 5cm in front rule was introduced I rode 7.5cm in front of the BB on a conventional saddle.
This equates to about 2.5cm in front on an Adamo which were not available back then.

The further forward you go the more stress you place on the knees as the hip muscles fire up when the knee is still very bent.
The further back you go the less stress.

Seat height is very critical when that far forward as it closes up the knee even more if it is a little low.
When you are that far forward, the hips fire before the quads, when you are far back, the quads fire before the hips, so it is a total inversion of timing compared to a road position.

You will find that unless you have something weird about you, directly on top of the BB is about as far forward as most people need go.