This is complete bullshit. Pretty much everything in original Sol B saw through invis, including kobolds. Just because Daybreak has gimped the game and made everything easy mode doesn't make it accurate.
There's plenty of proof out there, but here's an archive of Nagafen's Lair from eqatlas:
Nagafen's Lair -- EQ Atlas
This dungeon is generally regarded as one of the two toughest dungeons in all of Antonica. There are many specific dangers that I will describe below, however there are some general dangers as well.
First is that everything in this zone sees through invisibility, which means that corpse retrieval and quickly moving through the dungeon are not really possible. You will need to fight your way through everything you meet in order to move further in the dungeon.[/QUO
TE]
Gotta agree here. I don't remember once inviting to a spot in SolB. Not in the many hours spent there.
But it's fine to do on TLP. I'll confirm that the zone was permacamped way more than guk was in classic so it was safe more than guk was just because of everything being killed instantly.
Might muddle your memories confusing these two parts.