I switched my 22/32/44 3-ring setup to a 22/32/chainguide-bashguard setup. I've heard that you can "lockout" your front derailleur to keep it from shifting into the 3rd spot where the big ring used to be? It's not a big deal since I doubt I'll forget I don't have a big ring, but if you can set a limiter or something I'd like to do it just to do it- can this really be done? I was re-adjusting my front derailleur yesterday and couldn't figure out how this is could be possible...

thanks