Frequency Hopping

Hello,
i’m working on a 2G network and we try to investigate some new features.
I have been presented a new type of allocation called ad hoc.
It works as follows:
You don’t set some predefined list such as 1*1 or 1*3 patterns. You get lists on a cell basis depending on the number of TRX the cell gets.
The lists are provided by an AFP.
I would like to know if some of you have heard about this type of allocation (presented by the vendor as very spectral efficient) and if you know some networks where it’s implemented and is it working good.

Thanks.