Some of our US friends had the same inclination. But with multiple unfamiliar runways/taxi patterns (to we the infrequent visitors) at some of these places, it could be quite a challenge after pushback. I had no hesitation in setting park brake while we did EFB performance, reprogrammed FMC, reset MCP etc etc and rebriefed taxi routes. Not too popular sometimes with ATC, but better safe than sorry.
I am with Phantom. If the performance figures change, park the aircraft and get everyone on the flight deck involved. Changing the plan involves examining the consequences to ensure that there are no safety issues, sometimes hard to do when one's head has been focused on a different plan of action.
Qatar Airways now uses a checklist when any performance or runway items change after the initial planning. Good move on their part. Concerning this accident, thinking the #T1 issue is going to have a bearing though can't get my head around taking off with 2600 TORA off a wet runway for an 11:30 flight.