That dipole is interesting. Very interesting. You can change it for either horizontal or vertical polarization and for 2m that would be super cool for portable SSB as well as FM.
I have one concern with it, regarding how the dipole legs thread into the PVC and make contact with the brass screws. I understand the reasoning behind this and see the concept, but I would worry about oxidation causing a problem, not to mention each time you thread it together it will want to go a little further. So eventually you either bend the brass screws or the legs are loose in their threads. Either way after a few dis/assemblies the antenna would be mechanically or electrically getting weak.
I'm letting it sink how to make this better without soldering directly to the copper legs. My thinking is towards making something shouldered so that as you screw in the legs you make solid contact with a ring. Just not sure how to do it yet.
Also occurred to me to use 3/4" NPT PVC instead of 1/2" slip fit (e.g. glued to threaded adapter) into the 'T' and add a 3/4-1/2" metal bushing (copper if it exist, this is where you would solder the coax ends). Then the whole threaded socket would be the connection for the legs.
"Why does the U.S. care which flag will be hoisted on a small piece of land thousands of miles away?" -- Ron Paul