Bob Connelly's zone blocking technique was very passive. It was about letting the defender make a move and then trying to use his momentum against him to force him out of the play. It failed miserably because the SEC is not a passive league like the Pac 10 (Connelly and Price came from Washington State, of course).
Zone blocking can be an aggressive scheme that knocks the Dline back off the line of scrimmage. At its basic level, two lineman fire off the ball and engage a zone, not a specific defender. Whatever defender that is in that zone gets blocked, and once he is blocked by one of the Olinemen, the other continues on to the next level to engage the LB. When it's done right, it is a thing of beauty. The RB gets up the field quickly and makes a quick cut when he sees a seam open in the line. Of course, any good offense will hammer the D with a zone scheme and then when the D begins to cheat the gaps, the O will hit them with a power man blocking play. It's the pro-style offense at it's finest. Every play has a play off of it to keep the defense honest.
Never worry about anything close to Bob Connelly getting near an Alabama offense as long as Nick Saban is in charge.