The woofer surrounds were completely gone. I'm in the process of paying to have all the 2214Hs fixed. The tweeters I've tested have been OK, but really dirty. The cabinets -- I'm refinishing.
Your second paragraph may be the 'clincher', and I may come to the same conclusion. BUT, the fact that no one has directly addressed in any detail all 3 of my questions, makes me think that maybe not many LH members have pondered something like your statement, "The 2 14"ers will have more cone area than a single 15 - maybe about the same as single 18 - BUT that doesn't mean it will work better than a single 18." BUT, what if it does? The only way to find out is to try. However, at the end of the day, I do agree the JBL folks were absolutely without equal, wrt design and build. However, I also think that in the 60s and 70s they were a lot more open to various combinations than we seem to be today -- both in their 'custom' speaker enhancements and their 'kits', as well.
I hate that I got sucked into this JBL vortex!
Different drivers with different horns with different adapters with different voice coils with different cones with different frequency dividers with different dome materials with different .............!!!!!!!!!!!!!!!!!
But, as you can see it doesn't bother me ...............bother me...................bother me.................bother me.
Greg