If we talk about an OW pitch on a long multipitch climb, I have always been curious about the Monster Offwidth on Freerider/Golden Gate. My impression is it goes from narrow to wide bottom to top. I always thought bombay OW is insecure and hard, but it's hard to fall out of an OW that keeps opening up. #6/#7 should be relatively comfortable for most people as that's a size eveyone can get their entire leg inside. Many different resting positions depending on one's size can come out of it. However, every video I watched made that pitch sound like a gruesome fight. What makes it so hard?
The Monster is pretty steadily #6 the whole way. Most people traverse in directly to the sixes section ("the downclimb") but you can also take the Bermuda Dunes Variation that does open up from 4 to 6 rather quickly. There is one pod where it opens up for a body length where is 6 is unreliable. What makes it so hard? It's an offwidth. It's sustained for 200 feet. It's not exactly "roadside". That said, Jim Reynolds rope soloed it without a #6 and I think some other guy free-handed it too....