MAP11 has section identical to DSV4 MAP02

This may already be known. Map11, behind the blue door, has a section that is identical to another wad. The textures are changed and some
objects and monsters are moved, but it is mostly identical.
It is the area with a walkway, and a moat on each side, machine gunners behind bars, with little winding stairs to get back up.
Even the maze behind it and the traps are identical.

See Map11 behind the blue door.
See DSV4: The Revolution. (32 level wad) by Kaiser (Deathman)
8-4-2002, Ammo Lab, MAP02

That might be intentional

Yeah, intentional or not, the original author can do that.

So Kaiser did MAP11. I tried to verify that, but starting at the FreeDoom Forum info post, I could not find the list of levels and who did them.