Has someone looked through the files and spotted where the check for a separating body of water, in order to be able to create a colony, is?

I'd like to use the feature to relieve myself from micromanagement, without being locked to using islands. I know you can gift your towns to an existing colony, but that still requires that you've set up two cities on another continent, which eliminates the ability to use stuff like Pangaea with it.

It should be easy, just removing that check, but I haven't bothered having a try myself yet. After a long hiatus, I can barely remember basic game mechanics, even. Still need to put in my regular fixes, now that I noticed the people cannot see horses without researching stuff that uses them...