John Smith wrote:
What would happen if you isolated that second driven element from the boom
(the one you are effecting the phase-shift in, and added another reflector
( naturally it is in proper phase) behind it? Could you get the best of two
worlds? The advantage of the phase-shift plus a FB ratio?

That's just the sort of thing antenna modeling programs are for. And
they're good at it.

Roy Lewallen, W7EL