Maybe I'm not understanding correctly. When you say "chewing" the harness off, do you mean the actual harnes itself? Or the attatchment? Or the seatbelt?
I can only speak for the Ruff Rider...CORRECTLY fitted. Harness ONLY. If it has been
fitted properly I'm not seeing how a dog could get part of his jaw underneath to actually chew. He'd practically have to break his own neck to do it. Then, he'd have to come in on top of the harness and scrape or gnaw from the top? Surely this would be heard?
Like I said, mine NEVER tried, so I truly AM curious as to how this was done. C'mon, chewin' houdini owners:

explain for this curious, befuddled DA.