YMG,
Yes... I plot the field points (which always include exterior traverse points), draw the breaklines and boundary, then window the points of interest for the TIN. In the process of windowing, some of the exterior and unwanted points are included in the selection.
Consequently, a TIN is built on all points chosen, but then it removes all those TIN's that lay outside the boundary. They were accidental and unwanted.
The result is that you only have TIN's that are within the boundary limits, and you haven't needed to be very picky about selecting its points... simply square-window the area.
I don't quite understand the method that you have described, and I guess you have never understood my objective as well. For myself, the purpose of a boundary is to allow a relaxed and quick selection.
I should have had a clue when, some time back, you said that you always draw your boundary after having done the contours. Where as, I was proposing that the boundary be drawn before building the TIN. I also thought it was odd that you were bothered by my referring to them as Bogus TIN's. Maybe the word "boundary" should not have been used. It is a TIN and Contours Limit-Line.
Rick