I thought the Greg Golson and Anthony Hewitt things would be controversial, but instead it seems to be Lou Marson who is the controversial grade on the Phillies list.
Maybe I should go with B- instead of C+, but I really can't see it higher than that right now. I want to see more than just one high batting average season out of him before concluding that his BABIP this year was not a fluke. That said, someone in the thread below mentioned Suzuki as a comp, and I can see that as a possibility. If you want to get REALLY optimistic, you could point out some parallels between Marson and Geovany Soto, who didn't show much power early in his career but did have good plate discipline. Of course you could also point out numerous promising young catchers who fail to build on a good season and fizzle out.
I will think on it more and may upgrade to B-, but I think some Phillies fans need to take a step back and look at it a bit more objectively.