ABAT!
Read my post again please. I didn't say THEY should have investigated further I said that I would have. I certainly don't condemn them for applying the MEL and may well have done so myself.
Their mistake was not to cross refer to RAT sensing! It makes sense that if you de-activate the probe heat then the sensing for that system may be affected. It is after all, calibrated to indicate correctly when heat is applied.
In effect they should have applied 2 MEL refs. One of which would have indicated that the TMS was (or should be considered) inop.
The report indicates that the FO was pre-occupied with the fact that the TO would be with manual thrust. Had he known this from the onset he MAY have realised that the flaps/slats were not set.