I used to think it was BS until I saw it happen.

My dad had a 1980 Crew Cab dually with a 360. This was 2003-2004 or so and it only had 70K miles on it, it had a fair sized cam in it and doug thorley headers. It had been used alot as a tow vehicle and it picked up a miss and it turned out to be a bad exhaust valve. Well I tore it down and he had the heads redone. I put it all back together and fired it up. I warmed it up and shut it down, I had some things to take care of on it so I retightened some things and tried to fire it back up. It cranked like it had no compression and would barelly try to fire. Kind of stumped I called it a day. Well my dad messes with it and figures out it will start if you put oil in the cylinders and it will kind of run...run like it doesn't have any compression. Soooooo it can happen even if you think it is BS lol.