(a) considerations of BFL, unbalancing, overspeed schedules, etc., are all made before the takeoff as part of the performance assessment. This is done either in the preparation of RTOW tables/charts by the ops engineering folk, or by the pilot in those operations which impose that task on the crew.
(b) if the takeoff is accel-stop-limited then, in the GO situation, if the sums have been done acceptably, aircraft and pilot performance and weather are reasonably similar to the certification expectations ... then it should be a matter of just flying the aircraft through the exercise.
(c) if the riders attached to (b) don't apply then, just perhaps, the crew and operator have their collective necks on the line ?