The only way a clean tank would really stress a BP out, is if the tank was so dirty that after you clean it, it looks completely different. Then I would imagine the BP would think he/she is in a different environment and would need to acclimate. More than likely your BP will go to the bathroom after a freshly cleaned tank.
Handling technically stresses the snake, so after he/she is out and about for a bit they have a tendency to roam, then they will go back to normal.