Regardless the MKII GT3 does 7.54 even without Roehl driving and that's with ~400 horsepower and less weight than this new 997 S. Given that there's no way the 997 S is going to do 7.56.
Well, we have not really talked about whether Porsche is still under rating its engines and how the new active suspension system works. The latter is somewhat of an interesting proposition. CF seems to very confident in this lap time, as he has not offered much of an explanation at all.
On Ferrari laptimes: Does Ferrari actually test on the Nurburgring? It would make sense if Porsches are somewhat more optimized for running at the ring in terms of suspension settings, gearing etc..
The real question is whether or not the 993 based GT2 engines were underated to the same degree as the current model GT3 and GT2 which ARE undoubtedly underrated.
The torque figures on each car might be of minor interest as well...