Nevermind, maybe it does make sense. Only have to take out one pylon to take out the whole bridge post 1919. LOL, I won't tell where I though was the best place to put explosives with an untrained mind and he found this info on the internet.
Just like I thought no demolition expert needed.
It also sounds like it was a disaster waiting to happen and if the work that was being done affected anything structural (which is entirely possible), then it could easily have resulted in this disaster.