Is a 'Real' Vulcan Grab Possible?

Occluding both carotid arteries is different from a carotid sinus massage. If you block, or at least substantially diminish, flow through the the carotids you are effectively starving the brain of blood, and that can definitely knock somebody out. It’s one of the reasons they tell you to only massage one carotid sinus at a time.
The carotid sinuses, on the other hand, has baroreceptors (pressure sensors) that act through a reflex loop to decrease (when an increase in blood pressure is sensed) or increase (when a decrease in blood pressures is sensed) heart rate. This can cause unconsciousness in people who have a hyperactive response.

I know I’ve put my younger brother on the floor in a fair amount of pain by trying to replicate the nerve pinch.

I don’t believe you. No younger brother would think anything done by their older brother was ‘fair.’

sister he was always the gullible one of the family, as evidenced by the peeing on the electric fence episode.

scooped…

There does seem to be some potential for AI and biological intelligence to psychically connect. Remember Spock successfully mind melded with both V’ger, and Nomad.

Unlike Nomad, Data is advanced enough he can take a paradox. Hell he might have ignored his very own ethical programming and attempted to shot a man with a Varon T Disrupter, at one point and then lied about it. That guy had it coming. Imagine Nomad attempting that decision.

Data did not ignore his ethical programming by deciding to shoot the collector, whose name was Fajo if I recall. His rule against killing cannot be absolute; otherwise he could not serve in a combat post on a starship. He recognized that he had made an error earlier in not killing Fajo. That is, he had treated his imprisonment as a simple crime, when in fact it was more akin to being a prisoner of war. Once he put Fajo in the correct category, he knew what to do.