Surely all talk of using them is just further evidence that it won't happen.
If he just randomly set one off it might make people sit up, but now he just seems like a lout shouting at a doorman how he's gonna come back and shoot.
I don't think we can make that assumption. Drawing a line as publicly and as clearly as he has leaves no other place to go if they are used anyway. Do I think he would push the button if that happened? Probably not, but there would be a reaction more severe than we have seen so far.
As I said earlier, if this step is going to be taken then it needs to be done when there is sufficient stock in place in Ukraine to make it worthwhile and genuinely effective - ie: we aren't talking about 00s of missiles total used in dribs and drabs - and we in NATO need to be more prepared for any likely reaction.
The drone attack on the ammo dump, on top of the other successful deep strike drone attacks showed this need is not as pressing as is claimed and there are alternatives that could be developed instead (and indeed might be) - Ukraine already uses Neptun for land attack within Russia (and is upgrading the range considerably), and one would imagine a reverse-engineered Kinzhal (which is well within their capabilities) would be both deadly and ironic.