Okay, I'm compelled to chime in on this one.

The ARRL antenna book has a "cookbook" design for using 300 ohm twinlead
to make folded dipoles. In my 18th edition its the first thing in
Chapter 15 "Portable Antennas", pg 15-1.

It uses an open stub of the same 300 ohm twinlead to match to a 50 ohm
coax. You could just as easily omit the stub and run the twinlead to a
tuner.

I have one made from Radio Shack 300 ohm wire. After cutting per the
cookbook, including the stub, it tunes up perfectly on 3.775, only 25 kc
up from the stated center frequency.

The drawbacks to the design:
1)The stub, which is 37 feet long for 80 meters. You can replace the
stub with a capacitor, but I had the twinlead on hand....and was
interested in the design.

2)The fragility of the twinlead. Dave, KC1DI, mentioned that in his post
too. I have the center taped to a foot-long chunk of electrical PVC, and
a bit of nylon cord helping to support the feedline drop. That's been
sufficient for two years, so far.

3)Power. I have no idea if this thing would stand up to a kilowatt, but
it works fine at 100 watts. I'd be afraid to "smoke test" it....

Twisting, flopping, and drooping seem to make no difference. It plays
as well as the inverted vee it replaced, but except for a better SWR
bandwidth, its just a dipole. With the stub match, and a 90 foot coax
run back to the shack, the SWR is under 2:1 from about 3625 to about
3910, but my rig's internal tuner handles the edges easily. The SWR
seems to rise more sharply on the higher end of the band. I don't
notice any changes in SWR when its wet--not yet anyway.

On the positive side, the antenna is relatively light, and you can drop
the 300 ohm feeder right to ground level rather than pulling 20 lbs of
coax 40 feet up. And if you have a spool of twinlead sitting
around--its free.

I keep mine because its already in place, and it works. When it falls
out of the tree, I might follow Dave's advice and put up a regular
dipole fed with the twinlead.

Its only unique quality is a slightly wider SWR bandwidth.

Have fun..

73
Keith, W4KAZ