Maurice, I think you're probably right. I imagine that might be the difference between what someone calls a 'rebloomer' and a non-rebloomer is probably the touchiness of the plant. Some probably do better with competition that others, or they may make slightly better use of their growing conditions, or they might process nutrients slightly more efficiently than the daylily next to it...hard to say. Either way, I noticed that in my garden, plants in similar growing conditions (i.e. in the same garden bed) performed differently.
My 'Thanks Two Friends' is right next to several other daylilies that did not rebloom--in fact, it was right next to my 'Jungle Beauty' which suffered and ended up losing half its buds/branches, yet 'Thanks Two Friends' had instant rebloom and flourished.
@kousa , you may also be interested in blooms that are
bud builders, of which I had atleast two this year:
...not truly rebloomers, of course, but since they are bud-builders, it's not too unlike having a plant with instant rebloom...sort of.
