I wouldn't say a "slog" so much as, it has a huge degree of variance, unlike most other raids in the game, you can't just click a button and be teleported in, you need to meet a series of requirements, and then you will be allowed in, and while the raid itself is fairly easy, it is also punishing of mistakes, primarily by normal Rez being disallowed inside of BA, and the last boss will regularly suck people entirely out of the raid if they are dead or otherwise fail the mechanic which makes it extra punishing, the general rule is to play it safe and let the bosses take longer but execute all mechanics correctly and (hopefully) nobody dies, ideally you will go bonkers kill fast while playing it safe, but if forced to choose between either slow safety and speedy recklessness, the priority goes for safety, as only one boss inside BA has an enrage so it doesn't *truly* matter if the fights are slow most of the time.
Occasionally you also get grievers in BA, it's rare but it is known to happen, and you can't do anything about those, other than hope they die and don't get rezzed, I had a particularly bad run where two grievers were purposefully messing with the 2nd-to-last boss and caused most of the raid to die, it was also when I learned that Healer LB3 bypasses BA's rez limitation, good times... after the raid the run lead went on voice chat all, "I am not going to tell you to just report those guys, or what their names were, because that would be bridgading, which is against ToS... but if you were killed by their actions, that constitutes MPK, and thus it wouldn't be unreasonable if you reported them for this.", just the most "Legally speaking, I will not incriminate myself, but..." language that made me laugh.
