TL;DR: The "fix" for Scorching Heat on March 27 doesn't fix the root issue and instead introduces new problems.

Originally, when I ran this dungeon on PTS, whenever Valinna teleported away from me (the tank), I would immediately go chasing after her, since that's just what I do by default when any boss teleports away.

Chasing after her after a teleport caused issues; for example:

• Sometimes other players would leave an Immolation Trap in the way.
• There might sometimes be jostling for position as I try to position the cone at the new location while others are trying to position their Rain or Trap.
• The boss would sometimes immediately start running back to me after teleporting (instead of doing another mechanic for a couple of seconds), and I end up meeting up with the boss in the middle of the room (which I don't like because it means awkward placements of mechanics and cone).

So by the time the dungeon hit Live, I decided that chasing after her wasn't the best of ideas, and I decided that it would be better to just let the boss come back to me. It solves all of the problems associated with chasing the boss, and she moves pretty quickly--if someone had dropped a DK Standard, for example, she'll come right back into it after teleporting.

But when I changed strategies on this fight, I started to notice the bug that @frozzzen101 wrote about in post #15 of the PTS thread (this was after it had gone Live, which is why I didn't notice it during PTS). That Valinna just doesn't move (except for her teleports). This doesn't happen all the time--there are many pulls where she's quite nimble and quickly runs back to me after teleporting. But there are also many pulls where she just plants her feet and refuses to come to the tank.

When she's stuck and refuses to come back to the tank (and the tank doesn't chase after her), she only cast her ranged light attacks, since her cone is out of range. (I did not, however, observe any of the other claims in that PTS post--the cone appears to be the only mechanic that she skips, due to it being out of range.)

So, on Monday, when the first incremental was posted with the patch note saying that she now casts her cone as intended, I assumed that it meant that this was a fix for the Valinna-refusing-to-come-to-the-tank bug. But it was not. The root problem is still there, where she would refuse to come to the tank, and so if she teleports away out of range, she remains out of range.

Instead, what the "fix" did was to make her cast the cone even if she is out of range. This, frankly, is the wrong fix.

• This doesn't address the root problem, which is that she would inexplicably decide to not move to the tank.
• If she does the cone out of range, the cone is, well, still out of range. After Monday's patch, she would teleport away from me and then immediately cone, and I could just stand there ignoring it because the cone is out of range and doesn't reach me. There's a good reason for there being a range check on the cone cast, and removing that range check just makes her do silly things like casting her cone at someone who can't be hit by it.
• This introduces new problems, because even on the pulls where she doesn't get stuck and she does freely move to the tank, she will now do the cone out of range anyway. There were a couple of times where she teleported away and immediately did the cone at the tank who is now out of range due to her teleport, and then after the cone, she runs back into range of the tank. There was even one case where she teleported away, started to run back to me, and then did the cone before she got close enough to actually hit me with it.

This "fix" on Monday is just plain wrong. It fails to address the root issue and instead removes a range-check that should not have been removed. Now she'll cast the cone when it can't hit anyone. Okay, sure, this can create some temporary area of denial, but it's pretty easy to just stand on her flank--we never once had her cone hit any player when she teleported away and coned the out-of-range tank.

But this whole thing has also called into question the purpose of her teleports. Frankly, it feels like there was a checklist of things that modern boss fights must have, and this was someone's way of ticking off the "boss should be mobile" checkbox. But I fail to see the point of these teleports. When she doesn't have the problem of rooting herself and refusing to come to the tank, she runs back fast enough that it's way easier and cleaner to just let her run back--she's usually back before our ground AoEs expire. And when she does root herself in place, it means her main anti-tank ability is out of range (unless the tank is stupid enough to chase after her, as I was during PTS).