Im currently working as a Spot Op on a Equity musical (gotta pay the bills, right?) and the calling goes like this :
During tech week, each Op got a sheet with all the cues written out, nice and detailed, with the cue number as well as with "LX GO" it went with.
For the opening night run, just to refresh us a bit, we'd get such calls as "Standby for Spot Cue 34 on Frankie" and we would generally remember, and peek at our sheet, before getting in position.
After opening night and all through the run, we've now only been receiving the cue-number and have pretty much memorized all 70 of our cues.
Its a good system, I like it, and I will probably use it if I SM a show and the lighting designer agrees to it.