Yeah, I agree with Walt. If a toe-punch kills them, it's saving you the cull that's going to happen in a day anyways. I've toed punched thousands of chicks--not one death. If someone's actually lost a chick, I wonder if they didn't toe-punch the toe as opposed to the web.
Right from day 1. Often, upon inspection, the little piece of skin might be hanging on a tad underneath. This is what causes the hole to "close". If it scabs back in, it has the chance of healing, but a hole without skin tag will not close. The skin tag just quick pinches right off, and they're none the wiser. I have a piece of paper towel on which is a little pile of blood stop powder. I punch the toe, pinch the tag, and then dip the foot in the powder. This isn't out of concern for the chick, because, of itself, the wound is outstandingly minor and will heal readily. I do it to stop the sight of red from goading on other chicks from tasting their neighbors.
It's also that we have too many chicks from too many pairings. I can't not put them together. I don't brood by pairing but by week. All of the chicks have to go together. From the incubator, I sort them into boxes according to breeding, to-punch, and then bring the group to the brooding facility.
At two weeks I go over the whole hatch, inspect, cull again, if necessary, and wing-band. I never mess with leg bands. They fall off to easily, and I really don't have the time to replace them as they grow, I'd have to do it every week. Our hatching spans over a period of fourteen weeks, that would be nuts.
My buddy, Brian, wing-bands day 1 and nothing but, but I'm worried about piercing muscle. If it happens, when they're older they can't open their wing fully. By two weeks, I find that they are easy to wing band.