They did something somewhat similar in the 6.1 MSQ.
SPOILER
The forbidden part of the library in Sharlayan is a room that you enter once for maybe 5 minutes to click on 2 objects and watch a cutscene, after that the room is completely inaccessible.

Now that's nowhere near as much work as they put into G Warrior but someone still designed a room that gets used once and then can't even be entered again.