As a data point: I use Scala + IntelliJ and I've personally actually turned this off. If you have a half-way decent type system I tend to find that it just gets

As a data point: I use Scala + IntelliJ and I've personally actually turned this off. If you have a half-way decent type system I tend to find that it just gets in the way -- at least if things have reasonable names. (This is obviously a very personal preference and depends on whether it's a code base you're already familiar with, etc. etc.)