Pelosi withholds formal notification -- What is her game?

OK, some tentative thoughts, I can afford to express uncertainty, mediated by the influence of Buffalo Trace bourbon (can I get a sponsorship deal?).

I don't understand the argument that Trump hasn't been impeached until Pelosi delivers the documents to the Senate. I haven't seen a sound constitutionally based argument for that. Anyway, I don't see any reason to think she won't deliver them eventually, so what's the point of talking about a strategy of temporary manoeuvring as though it's an end game, a permanent condition? Is any serious constitutional scholar making this argument?

I don't think the argument that Pelosi's withholding formal notification because the Democrats have a weak case will fly. Notice her language of asking for fair rules? That contrasts with McConnell's statement that he'll let the defence tell him how to run the trial. She's as aware as us that he's unlikely to get convicted, so this must be a play for public perception, I think. What will the uncommitted find more appealing, assuming they pay any attention, a plea for fairness or a promise to rig the process?

Beyond that, what's Pelosi's game? She's an expert political strategist, and I'm not, so I'm guessing, no more. Again, we have to assume she knows the Senate isn't going to convict, so she has to be going for something else. The simplest answer, I think, is again public perception. McConnell wants no witnesses, so he must be scared of what they'll say. So I think she's simply angling for witnesses.

Remember, while you're a political junkie who's been obsessively following everything so far, there are millions of Americans who haven't, but might now that the President has actually been impeached. In short, this is surely a political ploy oriented toward the 2020 election which I don't think will shock anyone.

Will it work? Damn, who knows? McConnell is the king of winning by standing pat, as he showed with the Merrick Garland nomination. And he can simply keep repeating that the Senate sets its own rules; the House doesn't set rules for the Senate. Will that simple clear argument defeat the simple clear argument of fairness? If I had any idea, I'd be a good political strategist. But I'm really not, so I have no idea. But I think if you consistently wagered on Pelosi you'd win more often than if you consistently wagered on McConnell.