Another great When is an elephant not an elephant? argument!Been "loads" of fun listening to this and I'd have to say Niklas has got you all ("traindrivers" and otherwise) beat for "in the trenches" empiricism and apparently his research didn't require much more than a cheap slide caliper. When everything's "nominal" there are a heck of a lot of special cases each with its own specific risk factor which our many "take it on authority" gurus seem unable to pin down.

jack