there’s nothing much about this parameter. It will only favor the allocation of a call on a TCH which has the highest number of hopping frequencies.
The idea is to put the call on a TCH which provides the maximum frequency diversity.
Since all TRX, except BCCH, are hopping on the same number of freq. (in a default usage of SFH), this parameter won’t have much influence on your bss.
Cheers
pix