That's all very true, but for people like me that have taken off the rear muffler and like that look, it would give the option of maybe a bit more noise without being obnoxious loud like it would be with a centre pipe and no rear muffler. Like if I fit a centre pipe, then I will have to buy a rear slip on muffler to quieten it down a bit.
And its good fun to play with stuff and do stupid things just for the sake of it.
I was thinking even if the piece did fall in muffler, it would be smaller than the hole you just drilled and a magnet on a stick thing would probably just lift it out with a bit of juggling.
I am tempted to try this to see how it changes the sound, you would get two different notes combined together, the exhaust gas taking the old path and the gas taking the new path both hitting each other to create a whole new sound like no one has ever heard ( mad scientist hysterical laugh)