Harm wrote: ... 'OTOH, a program that evaluates every position as a
completely random number starts to play quite reasonable ches, once the
search reaches 8-10 ply. Because it is biased to seek out moves that lead
to pre-horizon nodes that have the largest number of legal moves, which
usually are the positions where the strongest pieces are still in its
possession.' ...
This is nothing but a probability based heuristic simulating a mobility
evaluation component. But having a working positional evaluation,
especially when also covering mobility, that randomizing method is not
orthogonal to the calculated much more appropriate knowledge. Thus you
will overlay a much better evaluation by a disturbing noise generator.
Nevertheless this approach might have advantages through the opening,
preventing some else working implementations of preinvestigated killer
combinations.