Thematically trench warfare would be awesome for Chaos Dwarfs, given their industrial nature. I could see a network of trenches radiating out from every CD stronghold in the Darklands.
The problem is making it work within the unit-block Warhammer rules. The game is built around blocks of troops clashing. Maybe in a Mordheim type skirmish scenario?
I love the idea, though.
Game wise I doubt it would work. But I could easily see chaos dwarf hiding in there trenches. send the hobgoblins over the top then draw the enemy towards the trenches then capture them.
The dark land are probably covered in trenches anyway from empty mass burial sites, to empty lava channels.
No army would use trench warfare in a pitched battle. It is only in some kind of defensive engagement it would be employed. Unless you are sitting on something the enemy wants, there is no reason why he would attack an entrenched army, much easier to just go around it and head for the objective. Dark Elves as an example would just let you sit there and head for the nearest village to plunder and take captives. If you entrenched at the village, well then you are sitting on something they really want…
One of the few historical incidents were an army attacks an entrenched army in more or less an “open” field, is the battle of Poltava, 1709, 300 years ago. A battle between Sweden and Russia, taking place deep inside Ukraina. Here a Swedish army attacked a Russian army in a heavily fortified camp because (amongst a host of other things) it blocked their supply lines, and grew stronger every day. The Russians did not have true trenches though, but a series of fortified small forts packed full of cannon.
i really like the idea however i agree that it would not fit into the game of warhammer but you could make some sort of scenario which included trench warfare
Glad that my post is inspiring so many comments!