cooldown spoilers to follow:
so I've had enough time to mull it over and, now I think it's time to talk about how actually, Bolaire had a goddamn point about Thjazi Fang.
Bolaire never stated he was evil, but he did firmly believe that Thjazi was willing to sacrifice a bunch of people towards his own ends, and also thought he was an asshole. (I think Hal said out loud that he could be an asshole so. Like. I don't think there's any point in arguing that latter point. even Thimble admitted he was really shitty to Bolaire.)
it was revealed in the cooldown that if the ritual had not gone well, that there wouldn't be a need for a battlemap of the Hallowed Round. that's cool! it's fucking chilling, too! there were something like 10 thousand people in and around the Hallowed Round!
now, in general, I do tend to take Brennan with a grain of salt, because he will 100% lie to the players. That said, given the powerful magic that we witnessed as part of the ceremony, I do believe him. A dragon woke up. Celestial beings were created. Plural. The proportional inverse of those is absolute devastation.
Bolaire believed he'd kill 10,000 people to save more, and while we don't know if that's true, I think being willing to risk 10,000 people to save the afterlife... is kind of what he was actually planning to do.
Yeah, the ceremony would have been smaller, so maybe if it went bad not all 10,000 will die, but these are very clearly very powerful forces going into the underworld, and he couldn't be sure that he wasn't putting everybody in that theater at risk. He just couldn't.
Furthermore, Mara said Thjazi was going to talk to Hal about it- but was he? his whole thing was compartmentalization.
and to be frank, by the time of the execution, he'd set things up so Hal would unknowingly use the paints in the Hallowed Round, while he was going to be whisked away to never see or speak with his family again. Especially since Mara was supposed to approach from a different angle, she would never have even come close to interacting with Hal. There was no need for him to actually talk to Hal about this. Better to ask forgiveness than permission, right?
Now, I might be wrong about that, but he had a chance to talk to Hal unobserved by others, and only ever even mentioned the paints after he spotted Mara, and decided he was going to have to take a more direct route to the underworld. Maybe he intended to talk about it later, who knows, but- signs are ambiguous, at best.
And yes, the ink only just dried on the lease paper before Thjazi's arrest, but the plans to move into Dol-Makjar and use the Hallowed Round were also, very clearly, well underway. The paints were already being delivered to the Archenade. The wheels were already turning to move everything into place with Hal being none the wiser.
To say 'well everything went fine, so Thjazi isn't bad' is, frankly, a silly take. It was never really about Thjazi being bad in the first place* it was that he was willing to risk lives to do what he thought was right.
Which is very clearly true.
Does Bolaire think Thjazi was colder and more willing to be cruel and risk more lives than he actually was? Probably. His point of view is skewed by the way Thjazi treated him. He's probably not fully correct. But that doesn't mean he didn't have a point.
*barring that bit where Marisha seemed to get confused about the paint place working with the Sundered Houses (I think?) and seemed to think it meant Thjazi was working with the Sundered Houses, but I do think that was a genuine miscommunication/misunderstanding on her part.
