From @topisani on April 1, 2016 21:9

RTG2 needs to support working across dimensions. This means no static IBlockStates and alike for biomes and other things that could have different configurations across worlds

Copied from original issue: Team-RTG/1.9-Realistic-Terrain-Generation#46

From @srs-bsns on April 1, 2016 22:27

This will require a blacklist. RTG has no business in the Nether or the End, or in certain mod-added dimensions like The Deep Dark in ExtraUtilities. People will likely want the ability to add thier own blacklist entries as well.

From @topisani on April 1, 2016 22:44

Im just talking about suporting suporting it. its a whitelist, if it is even a list. it just means we or other mod devs can register a dimension that should have RTG world gen.

From @Zeno410 on April 1, 2016 23:23

I don't think we're going to do it anytime soon, but we should plan for it. At this point just use the idea "if we might want it to change in a dimension, don't use a static or a global".

Am I right in thinking this would be for things like Mystcraft support and RFTools support, where people might want to create dimensions with RTG terrain?

From @Zeno410 Yes, you're right.
From @topisani Also some multi world mods/plugins might need it