Jude Rosenstock said:The single-rail kick is much easier to judge. It's practically a mirror-image type shot. Even unexperienced kickers are going to get a safe here fairly often.
You freeze the cue-ball to the 8-ball and firstly, there is no guarantee you're getting that angle toward the necessary corner pocket. You could freeze slightly to the right-side of the 8-ball and that option no longer exists (just to play devil's advocate). Secondly, the angle of approach for the two-rail kick diminishes the probability you'll leave him safe. You have to hit your target full in the face otherwise, the cue-ball is going to be free and judging such an accurate hit in a two-railer is really really tough.
Most players are going to lower their expectations, get the legal hit and hope to get lucky.
Jude,
I hear what you're saying and it has merit. I just don't see it as a higher percentage safe option.
Try the 2 rail kick. With the two balls where they are, it's a very easy kick. For that matter, the 1 rail kick safe is not a sure thing to get safe either...
Eric