>>Then we have the same rights to use verbs like zap, pack, suspend, wait etc and the listener needs to know what they mean to us, right?

If there ever were a Developer General tasked with public health/information science similar to the SG role and you were selected for such position- then yes, you ought to use concise jargon.

>>Besides, a medical decision is, IIRC, related to 1) diagnosis, 2) determining the course of action. A diagnosis is a conclusion; the latter is exactly what I was aiming at: a decision is a verdict or a chosen action ("I've decided to discuss this further"). So... the guy decided that it "now reduces risk", whereas it didn't, before he decided it?

That's not what either dictionary says. Take another look: conclusion is a synonym for decision in the Google citation. This distinction you insist on, isn't real.

>>Ambiguity doesn't need justification, it needs to be avoided.

Says the man who seeks it out! Seriously, apply Occam's Razor to the SG's decision and stop smoking now. ;-)