Given this is ruby code, I think it's acceptable, and well-structured enough to be understandable.

While the implementation itself might be a bit 'eugh' because of the meta-programming involved, there was enough thought put into code organisation to allow you to grep `RowType` to find the module that namespaces all these dynamically instantiated classes.

Hell, if the code in the tree was arranged correctly, then `tree | grep row_type` would give you the folder where they all lived.