BUG_ON doesn't fix a problem - it complains about one. It's a bit like
assert(!condition) in userspace - if you actually hit it, the program's
already doomed. The Linux kernel tries to keep going a bit, just because it's
difficult to get debug information after a panic, but this is _not_ fixing a
problem, and a tripped BUG_ON is _by definition_ a bug.
As such, the only disadvantage to extra BUG_ONs is the run-time overhead from