Here's the thing, all the 'sploded boxes I have seen were cracked on the carb side of that baffle plate in there, which leads me to believe that it is the air filter that is not releasing enough pressure fast enough and it blows up. So while I agree that more holes = more chance for pressure relase, it doesn't seem to happen that way.
OK someone with a drilled airbox go crack the throttle on startup so we can test the theory out
