You can postulate anything you want. However, I'm not going to put any faith in that postulation. Why not go all the way and suggest cutting charges on support beams as well?
I am sure you can appreciate the consequences of our differing positions.
If you are right, and the Middle Eastern, Islamic, felon, un-licensed plumbers were authorized to be working on the WTC sprinklers days before 9-11, then the consequences of investigating the sprinkler work are nil.
If I am right, and the sprinkler system was sabotaged, then the individuals responsible for sabotaging the sprinkler systems are responsible for more deaths than all the hijackers combined. The consequences of not investigating could be devastating.
More importantly, if the sprinkler systems were sabotaged, the same tactics are likely to be used in the future unless it is prevented.