I've used parallel fed "fan" dipoles for years.
But I've never bothered with legs for 15m..
Always used the 40 m legs for 15m.. Guess a habit back
from my novice days.. Back then, my old transmitters
would match either load no sweat.. No tuner required..
Heck, I didn't even use an SWR meter when I first
started.. :/ Never missed it either..
With my modern rigs, the match on 15m, using the
40m legs is usually a tad higher than I'd like for
S/S finals..
So I slap a tuner into the picture as a "line
flattener". Even a cheapy MFJ random wire tuner will
match that.. And most internal radio tuners could
probably handle it ok.
It's not too far off from being a 3/4 wave on 15m.
None of my radios have internal tuners, but
I have several stand alone tuners.