8178 made the comment:
"Some have said pre-turnaround but there were people still flying Tipos and other new designs in the beginning of turnaround so the pre 1996 seems to work. When 2M started everything really changed and the “Classics” were no longer competitive in the higher classes."

At the risk of exposing my ignorance, (I've been out of pattern since the mid '80s), could someone give me the Reader's Digest version basically explaining the difference between first, the old SPA pattern planes, (Taurus, Phoenix 1, then later SPA such as the Dirty Birdy), then later, (pre-1996) pattern planes, and finally the 2M planes of today, and why the older planes are no longer competative. I can guess it's because of the higher speed does not lend itself to turnaround, but it's just a guess. I've been out of the "loop" so long, I need a basic education about what's happened in the last 20 years. Please help.

This ought to bring everybody to the same starting point.