McCaw would miss the first three games of the Super 14, which kicks off this weekend, Gibson told Radio Live.
"Richie's obviously taking a sabbatical in that period - normally when All Blacks take sabbaticals it can be up to six months, so we're fortunate Richie's decided that he's only taking three weeks off.
"It's pretty good and a mark of the man, really."
A round four return would see McCaw step out against the Blues in Christchurch on March 6.
Local bookmakers have installed the Crusaders as competition favourites, the return of star first five-eighth Daniel Carter seen as key.
Carter was on his ill-fated French sabbatical last year when the seven-time champions somehow scraped into fourth place while struggling all campaign on attack.