I wouldn't say this is a re-hashed discussion. The issue is that are so many variables involved that it's hard to give a short definitive answer. It does make it a really good topic though. The only thing I'll mention is high walk rates in the minors(especially the lower levels) without power(or even a high average) to support it are often unsustainable. The guy that immediately pops into my head is Dwaine Bacon. The lower the level, the easier it is to take advantage of those who don't know how to pitch yet/the Neighborgalls of the world. As those pitchers get weeded out/improve, you're left standing up there waiting for the walk, and when it doesn't come, you don't have the primary skills to do anything with it. Pitchers get the scouting report to pound the zone on you, and you're done.