Fox up-throw -> up-air only hits me when I'm truly caught offguard, probably less than 10% of the time. It's pretty easy to DI away or out of it. Then I mash diagonal, jump, and airdodge at the proper time. If I'm not in a good position to airdodge, then I won't, of course.
Yeah, I'm pretty sure hitting upthrow->upair is at least as hard for fox as fox vs jiggs, if not harder. Peach can almost always get out if she DI's away..
@shrouded, as for SDI, practice a lot on upthrow-upair (have a friend help you maybe), I think I do slightly up and left or up and right. Apply the same thing to drills, except full left or full right does better on the ground. Generally if you can get out of the drill, it's a free nair out of shield, because foxes have it ingrained in their heads to drill shine->wavedash past, and the wavedash past part almost always gets them hit by nair. Sometimes I'll even turn around before shielding to make that happen more easily (after I smash DI)
Around mid percents, ask a good fox to upthrow-upair you and see if you can DI the throw while in your shield, then double jump->float away in time. In my set with SFAT, near the end I purposely let myself get grabbed a few extra times to demonstrate the jump->float out.
http://www.youtube.com/watch?v=H_-lis05Okw#t=7m11s
I do it twice over here
On an unrelated note, here's the jumping out when expecting a shine thing that I mentioned a little while ago. I was obviously trying to nair out of shield, but since he shined me and I was in the air, I knew I could shield his upsmash in time. If I had tried to shieldgrab, I would've gotten pooped on.
http://www.youtube.com/watch?v=H_-lis05Okw#t=6m43s
Yeah.. and if I had to critique myself, I'd say my combo execution game is really lacking.. there were many upairs I wanted to do that turned into panic bairs, and my edgeguarding kinda blew. But sometimes having a good defense is enough.