Every SM I have ever met has created or modified their own blocking. When I need to understand someone else's (for instance, when I'm taking over a show), I have them read aloud a page or two of their blocking to me while I follow the notation. That's all I need, since blocking is the same no matter what notation you use. Make a key for yourself, like the legend on a map: a page that reads "x" means cross, "this symbol" means sit down, "this symbol" means chair, etc. Don't feel that you "should" know what the Yale method is (since you didn't go to Yale), just ask your director for five minutes to read a couple of pages to you.
Has anyone else uploaded .pdf's of blocking examples? Does anyone else do blocking keys regularly?