I agree with everything you say here but if you read the OP post he is going for his Tech ticket. Once you get away from the crap on 11 meters dx becomes fun again and a lot easier with a simple dipole. If your goal is to remain on 11 meters then open your wallet because DX cost money.True...Yes, you can talk DX with a ground plane or dipole, but when the airways are crowded, you need all the help you can get to get thru the mess...And that's where a beam antenna will out perform any ground plane antenna out there since they magnify your power and signal...More elements you have, more signal you have getting magnified so people on the other end can hear you threw all the noise.
With a beam, you can hear stations in DX that otherwise you wouldn't even know was there...
And they work just as well for local stations if you have one with dual polarity so you can switch to vertical for local.
There is one downside to beams tho, and that is they are directional, so when local talking you may find yourself having to turn the house around allot to talk to your buddies in your area...
Again there is no reason not to put up a big beam, even in the ham bands but in keeping with the vein of this thread you don't need it as much once you get away from 11 meters (or the freeband above 405).