Training would not be necessary. Proper knowledge of damage would suffice. You have been helpful in that respect. Although I don't have the information on bomb radius or radial damage, I can conclude on my own 2 x 4,000 lb bombs dropped ~75 feet from the intended target doesn't do 2800 lbs of damage to that target.
Should be okay for town centers, but I have to leave it to the ordinance folks to say whether or not it is NERFED. I wouldn't have raised the question if it only took 2 x 4000 lb bombs to destroy a 2800 lb target, but it took 3. Look, I know that there are complex formulas that HTC has correct for the most part, otherwise I wouldn't have considered it a bug. So, if there is more detail information with respect to damage scaling related to blast distance for 4,000 lb bombs, here is the place to answer. Maybe Skuzzy should move the entire thread to the appropriate forum (realizing that there are much more important things for him to do, but for this specific question, it would be nice to have the information concise in one place).
I do appreciate the information immensely, and believe that others besides myself do also value this kind of discussion. Again, thank you for you swift responses.