According to The Wrestling Observer Newsletter, here are the latest details on the Vince McMahon/Kevin Owens did Vince blade or didnt he story following the headbutt angle on Smackdown. The internal story is that there was no blade involved nor was blood planned, but thats also the company line for the blood in the WrestleMania and Brock Lesnar matches. As far as those involved in setting up the angle know, there was no talk before the angle about blood or how to shoot if there was blood. Meltzer also notes that nobody was talking about blood beforehand but that if Vince wanted blood, he just as easily couldnt have told anyone ahead of time
Owens didnt lay in the headbutt that hard unless McMahon told him to, because nobody is going to head-butt a 72-year-old man that hard without being told to do so. Meltzer also notes that when watching the angle back, that you can see a line going down on Vinces forehead in the close-ups, and when Owens delivered the headbutt, the cut opened right on that line. As far as the close-up shots, the story there is that they were instructed to shoot close-ups to get Vinces face as he would sell the beating, but nobody knew it was going to have blood.
On TV, the idea of minimal blood is looked at as acceptable, but the blood wasnt that minimal and they still shot close-ups of it, because if Vince wants a close-up, theres going to be a close-up. Those who have been skeptical of the story note that if McMahon bladed before the angle, that he wouldnt tell anyone and that there was more blood than one would usually get from a head-butt.