Hey guys, its possible that I might just be late to the party, but I have been looking at this 4...b6?! move in the nimzo-indian on a few occasions recently and I have found many lines (many of which are theoretical novelties) which may be useful as surprise weapon to even shock opponents with strong preparation. On first glance, it is often not considered in many people's preparation since it looks like it allows the obvious e4. Even players such as penguingim1 have not prepped this b6 move to any significant depth (at least, thats what he said). As a result, I think I'm switching from 4...O-O to 4...b6.
Anyway, I think I'm going to make a study on the opening and if you want to join and learn it, pls message and I'll add you.