It's not even that. Reptile gets outpoked on block by Kitana all the time unless he uses elbow. If Kitana is in your face, doing 11, 33, f3, f21, whatever is -1 or better, Reptile HAS to elbow to deal with it. Trying to play footsies vs Kitana...forget it, Reptile won't even be able to touch her outside of whiff punishes. Too slow and not nearly enough range. And if elbow is blocked, bye-bye a lot of life.
The only saving grace is that Reptile does blow her up if she's too greedy on the advantage at -1, and even at 0, where random trade win takes over and at worst, Reptile's eating a d1. The knockdown can kill Kitana, though, because cutter can get blown up by forceball traps, and even if she fan farts out, Reptile can choose to make it hell to get back in or attempt to punish it. Luckily, Kitana can't just fan fart back in, either, because Reptile can just elbow before she goes over him and switch to the other side. Or if he's ballsy as all hell, just NJP the fuck out of her.
Yeah, don't let elbow online ruin you, because that's just online. Everywhere else, Reptile gets beaten pretty bad by Kitana up close. He has to risk his life to deal with her pressure...so what if elbow is 6 frames? It takes just 1 blocked elbow to put me down up to half my life, and the only big deal for eating one is the knockdown and dealing with his oki, which is all guesswork. I'm not gonna guess right 100% of the time if I knock you down, so none of my damage is guaranteed. You block elbow, it's all guaranteed damage.