confused why you think that was by design. I get that the plan was to stay home on the shooters, but once green was beat, there was time for people to rotate and have somebody at the rim to at least make it a difficult shot. On that drive, Fournier had really only two options, score, or pass to one of the corners. If ibaka was leaving his man, and whoever was guarding at the guy at the top would rotate to cover ibaka's man, there was no way Fournier could have passed behind his back.
But all that happened in second or so, so players would have to be extremely in sycn to pull it off. Perhaps, Nurse knowing that we are far from that kind of cohesion, decided to play it safe and avoid the 3pt shot, but an elite defensive team should be able to cover it and, hopefully, later in the season it won't happen again.
Green should've fouled Fournier once he went to the rim. leaving a 3 pt sideline shot while rotating to close penetration would be a game loosing mistake