We have two PRNGs in MCServer, MTRand and cNoise. Seeding a MTRand is a rather costly operation, definitely not good to do that too often while generating. cNoise is simple to seed, but plugins don't have access to it, so the function that uses it could not be exported to the API.
Ugh, those mineshafts go all the way to the void
Better fix that.
Wanna see something fun? Try setting height generator to Flat, FlatHeight to 2 and composition generator to SameBlock. Remove all structure generators and finishers except for Mineshafts.
Ugh, those mineshafts go all the way to the void

Wanna see something fun? Try setting height generator to Flat, FlatHeight to 2 and composition generator to SameBlock. Remove all structure generators and finishers except for Mineshafts.
Code:
[Generator]
Generator=Composable
BiomeGen=Constant
HeightGen=Flat
FlatHeight=2
CompositionGen=SameBlock
Structures=MineShafts
BiomeGenCacheSize=0
ConstantBiome=Plains
HeightGenCacheSize=0
SameBlockType=stone
SameBlockBedrocked=1
Finishers=