Well at least ChipTorque has confirmed that this can be done today - eliminating the MAF is available from an interceptor:
One of the most powerful functions that can be achieved using this variable structure is that of nested maps. Conceptually however, it can challenge even the most capable tuners.
Nesting maps can be achieved using the ‘Reserved In’ locations as a place to store the output from one map. This can then be used as the input to another map. A typical application of this would be to use a map with MAP In as a load variable, and TPS In as an input variable, to generate an approximation to a MAF signal. If this is achieved successfully it eliminates the need for a MAF sensor. The quasi-MAF signal can then be tuned in the regular manner and output to the ECU, which, in theory, would be none the wiser.
Not that I am any closer to figuring out how - but then again I don't need to just yet so no real pressure to.