in theory, it might be possible. You would have to make a feedhorn with waveguides that bring both signals together with the exact same phase (equal length of waveguide).I have 3 DIRECTV dishes with the images below. Could I stack two of them and have one lnb? Or is this just a really dumb question, I'm kind of a noob.

yes I think that's the one I remember, but could not remember what the result wasInteresting. There was a fellow in the NL a few years ago who placed 3 & 4 small ku dishes in a clover leaf pattern and built a tripod for prime focus lnbf. The before and after signal strengths showed that it worked pretty well.
www.sat4all.com
Helaas nog steeds geen beter signaal als met één TDS64 in standaard opstelling .