I'm not a frame builder, I don't play one on television, and it's been a long time since I stayed at a Holiday Inn Express, but I'm not convinced that using light gauged tubing necessarily compromises ride or durability.
I own, and have ridden frames built with 531P and 853, and I can't say I have complaints with the ride of any of them. I think that perhaps they have the reputation of being uncomfortable because the thinner gauge tubing is most commonly used on frames with tighter geometry (built for racing). I suspect the geometry has much more to do with the ride than the tubing gauge.
I should also note that my weight easily exceeds the published recommendations for the light gauge tubing. Despite this, I am unconcerned about the durability of the frames. Perhaps if I rode like a force of nature, things would be different. I suspect the reputation these have for not being durable is also (at least partially) attributable to them being used on racing bikes so often.
John (pondering the universe) Barry Mechanicsburg, PA, USA
--- On Wed, 7/7/10, EPL <firstname.lastname@example.org> wrote (snipped): ...
There are many ways to save weight on a complete bike which
do not compromise ride and durability the way light-gauged