Certification of the aircraft assumes that for a wet or dry runway, reverse is not required. However, in determining the minimum landing distance required for the configuration and conditions, the lack of available reverse thrust means an additional distance should be factored into the calculations. I assume that TAM's MEL refers to dispatch with an u/s T/R as requiring reference to additional landing distance required?
If the weather reported in an earlier post was correct at the time of landing, then the correct landing technique should have been as follows:-
correct land flap setting, approach speed close to Vref, firm touchdown on the touchdown point (and on centreline), immediate deployment of speedbrakes/spoilers, immediate application of wheelbrakes (auto or manual),selection of available reverse. The retardation should aim to bring the speed close to taxi speed before encountering the rubber deposits at the reciprocal touchdown point.
It is the task of the investigating authorities, to determine whether or not the above techniques were not used and if that is the reason for the overrun.They may determine that other factors such as runway surface condition or precipitation/contamination were causal factors.
Too many overruns are happening because of inappropriate technique. Perhaps the professional pilots amongst us, should ask their simulator instructor to allow them 5 minutes to practise a landing on a short runway in conditions such as turbulence with moderate rain. It is the best place to hone such skills - unfortunately simulator sessions are all-too-often box-ticking exercises with no time for developing basic skills.