Teitenblood fucking rule but I always thought they were more musically classed as Death Metal rather than Black Metal. Anyway, they fucking rule. Yea, that kind of thing needs to be a full on assault that doesn't break up into little bits and pieces. Quite a few bands seem to do that. I'm just listening to Mortuus Lunae which I quite like (nothing brilliant but good) but there's a bit too much let's-stop-for-a-spooky-break for mine.
It does matter if it's in context. Stridborg manage to keep a whole atmosphere going, from production to actual music, to make it work if there is a spooky-break.
Dungeon Synth I couldn't give a rat's about. I never bothered with Mortiis, apart from bits and pieces on CMI comps. If you're going to play synth music, do it properly. Fenriz's Neptune Towers is too underrated. I read a description from some wanker saying that he just leaned on a keyboard for half an hour which could not be further from the truth. He manages to stay true to his influences on both those albums.
Synth in BM has always been problematic. Good symphonic BM is a bit rare to my ears. Lymbonic Art did it best. I think The Eye is a good project too.