i had a buddy shoot a doe, behind my house a couple years ago. he shot a bit too far back, and called me to come help track her. at first, he tried to just let her lay. he saw where she went down, and wanted to hunt a while longer. a little buck came along, headed right for where he shot the doe. he figured the buck would bolt when it smelled blood. the buck hit the doe's blood trail, found the doe, and smacked her with his rack until she got up. he rousted her out of 2-3 beds before getting bored with her.
then theres the buck i got last year. nerves had me freaked, and i missed the first shot...right under his chest. he jumped to the side, and started sniffing around in the grass, trying to find my arrow, which was coated in blood from a doe i had shot the night before.
i really don't think a little blood makes any difference. now, a huge, old, skittish monster, that has been around the block a few years, might behave different, but i plan to shoot does as often as i can