I agree with 6L6X4, I think 5 minutes is a bit on the short side. People can and do get distracted; although I'm sure Audioholics would love to believe that the forum commands our undivided attention, sometimes the real world interrupts.
60 minutes is long enough to correct awkward language or typos, or perhaps to look up some detail (what was the model number of that disk player?), taking into consideration that we're running real lives here at the same time we're rambling on. I would even be OK with 30 minutes, but, hey, you have to pick a number, and 60 is just as good as far as that goes.
For me, I tend to ramble a bit, and my writing style is definitely old school; I believe in the power of editing to clarify a thought or opinion, and I went to school at a time when you typed your essay, and then got out the pencil, and then retyped it. I've been using computers for two decades, but never really got used to not seeing the big picture with computer text's limited window space and single page views. Maybe if I had been born 10 years later, but there's nothing I can do about that ;-)
I also almost married a writer, and she's a professional editor today.
I don't support indefinite edit times. Anything beyond an hour has potential to hurt the continuity of a discussion.
Appreciate the quick response from Gene to the parent post with a change, though. Obviously the feedback category isn't just window dressing; nice to see.