Dave that sucks, about your buddy meeting the tree.
Hope he was alright...

How do you know it was the conversion that did it, though? Maybe it was a little wet, or he was on shitty tires.... or just hauling too much ass.

That's not to discount your comment at all, I'm just looking for a possible explanation that so many people get away with not using a disc brake proportioning valve,
and so many FAQ's reccommend an action that obviously can be very dangerous.