I've seen leos bend their tails all sorts of ways. they can twitch the tip of it really fast too. So I figure that if they have the muscles to twitch that fast, they have the means to bend it near the tip. Also look at it. if it looks straight sometimes, and crooked others, you're fine. From what I've heard, kinks are apparent from birth (what I've been told, never wittnessed it myself). I'm pretty sure that kinks are always pointing the same way too, so if it switches directions, then it's not kinked. hope this helps!
Kev
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Kev
1.1.0 Tang Leopard Geckos: Marley, Mary
1.0.0 Normal Leopard Gecko: Toad
0.1.0 Colombian Rainbow Boa: Rambo
1 Beta: Malificent
0.1.0 Tri Australian Shepard: Nelly