Late last night, I was sitting around playing with my ropes and crabs and other climbing gear, and I realised that "guide plates" (Kong GiGi, BD ATC-Guide, Petzl Reverso etc.) are pretty much just ratchets (when used to belay from the top). So, I figured, why not use a garda hitch and save all of $20 instead?
So, yeah, the monetary savings are ridiculously small, so maybe that's no good reason to use it, and of course the garda is no good for belaying a leader, but is there any reason *not* to use it for belaying from the top?
The one issue that I'm aware of is that it's tricky to feed rope out of a loaded garda hitch. Are there other problems?