Kind of seems like the most fundamental part of building a secret tunnel would be to not post youtube videos about it, but what do I know.
I saw a video about 5150 (the studio) the other day, and Ed had to be kind of clandestine about the whole thing to get around permits and codes and whatnot. Officially, the last seven VH albums were recorded in Ed's Racquetball court. I suspect this guy means hidden, rather than secret. Otherwise, he might be in for some unexpected trouble.