personally, i put up with the pinching. the biting though is another matter. i'm on my second nursling. the only "cure" i've found for these problems is to look 'em straight in the eye, and tell them calmly and stronly "no pinching" or "no biting" or whatever, and then take them off. wait a very short time, like maybe a half minute, then try again, usually switch to the other side, just to reinforce that they hurt you on the one side, say to them, "ok, we will try again, remember, no pinching" or "no biting" again.
i tell ya, they are little at 8 or 9 months, but they understand way more than they let on. the get it. what i described above, it works for me.