Chiming in as requested Mike. I've never been a fan of primarily playing the two rail bank on the back ball in these situations. mostly because playing the head ball and forcing it towards my pocket is easier to control. This one shot also sends the back ball into my scoring zone, sometimes making both balls. In addition, the shot is far safer if struck reasonably well because the necessary draw on the cue ball assures the cue ball will be back up table.
The front ball will never be made on the shot where you send the cue ball three rails while playing the back ball. That shot has another problem. Double kiss potential. I stay away from this shot altogether. I also stay away from the force shot on the front ball if there are any possible obstructing balls the back ball can potentially glance off of and send something the wrong way. I must have a clear path for the back ball, otherwise I'd rather play the safety as Cincy mentioned.
As for table and pool ball conditions are concerned, they definitely play a role in the success or failure of any of these shots. Humidity is also part of the equation. Moisture reduces friction and it will result is less throw effect. Dirty balls increase the friction and cause the balls the throw more but that may not be so helpful either because there may be a higher likelihood of a double kiss occurring. Bottom line, you will want to know what to expect from table to table, hour to hour, day to day. These conditions continually change in the course of a few hours of continuous play. Chalk dust gets everywhere, slows the table and dirties the balls. The table may begin to play shorter and shorter. The player who recognizes these changes quickest has at least that much of an advantage over his opponent.
If you intend to play in the evening it may be a good idea to ask the houseman to give the balls and table the once over before play begins. The table and balls will likely be dirty by the time you arrive to play.
Tom