If +/- doesn't make a difference either way then I suppose it doesn't matter whether it's part of the scoring or not. Which on it's own sounds like an indictment against the stat. Advanced stats are a whole different world but I do like the fact that the are more directly reflective of a players performance. (Whereas +/- is more of a team derivative.)
With +/- at one end of the spectrum and advanced stats at the other, I think blocked shots fall right in the middle as an important (and easily understandable) part of today's game. Discard +/-, or keep it, but definitely consider phasing blocked shots in!