[tmm84]

This has been my personal experience. I came from a non-RoR background but I have done plenty of programming. The amount of clever solutions advanced ruby-ists come up with can be hard to comprehend and add to that the dynamic module resolution that rails provides it makes for a high amount of mental overhead when reasoning about what something should do when running. I get the whole this is slick and it eliminates boilerplate but that is only if you know what is going on, a new comer or non-ruby programmer is going to be sunk until they figure that out.

I have yet to find a decent book that isn't beginner (here's how to create a rails controller or let's define a class) or super advanced (so you wanna meta-program, hold my beer) on the topic of Ruby. So definitely getting devs up to speed on a Rails project that got clever is an uphill battle unless they are senior.