It neither sounds nuts, nor is nuts. I’m not sure who would have an interest in Meat Loaf’s living any longer or shorter, but it would nonetheless be fairly trivial to determine differential outcomes by selecting from different vax batches and/or by differential dosage for any given jab.
Generally, appointments are required days in advance, but even without recipient information long in advance, name, age, weight, SSN can be entered, with an on-hand vial number being spit back at the shot-giver as to which to use.
It’s all acknowledged to be a big experiment with these differential batch numbers and dosages. The manufacturers and CDC are certainly keeping all that under watchful eye.
I hope some kind soul can arrange for a dose from a placebo vial for my forced injection if it ever gets that far. They would by that time necessarily have knocked me out, so I likely won’t have any control over what’s going on.