Yeah! It's not fair! But no to player To UFO!
Once, in Phase 1, my 2 Condors (with basic weaponry) were cough up by 1 Alien's interceptor. I didn't even try to beat it manually. (Theoretically it's possible, but need a lot of practice). I was sure I'll lost my planes. And just press auto-resolve.
I was so confused, when result was - my win! O_o
I think it's not fair! When player don't know how to win manually, but auto-resolve - knows!
I think it's a hack - and don't use it.
P.S.
Air game - is a pleasure! It has a perfect balance in X-Division! But, maybe, it's bcs I've never played neither vanilla, nor XCE