Brooks, thank you for your well stated argument in favor of the return of the Extend tool. I couldn't have said it better myself!
As for me, I'm not an AutoCad refugee (although I've spoken with others who are about the Extend command), I am one who has been using the program in a certain way for several years now and the Extend command was part of my regular repertoire. The old adage "why fix it if it ain't broken" seems to fit well here. The Extend command was very functional because you could extend multiple lines within a given command, where you must now click and drag each line individually to the desired location. It's quite useful for setting up layout lines and grids and expanding those grid lines once they are established.
I would vote to return it to the next version of the program. Shall we put it to a forum-wide vote?