....if you should use a little running English on the cue ball and a firmer stroke with a 45 degree cut shot in a humid pool room. (Some say you should, especially if the balls are not extremely clean as they can get “Sticky”).
As others have said, your positional needs (weighed against the increased/decreased shot difficultly each of the positional options creates) will dictate the english and speed with which you need to hit this or any other shot.
If it is one of those rarer cases where both positional options are equally as good, then I would say to choose the one that you are personally most proficient with and have the highest success rate with. It's hard to argue with playing the percentages, for you.
If the question is which one should you try to get more proficient with because it is most ideal, as in which one should you use when you are equally proficient with both, then there is still a bit of debate on the matter. With no side spin on the cue ball you don't have any cue ball squirt/deflection you have to deal with, but then you have cut induced throw you have to deal with. If you use the proper amount of gearing english you don't have any cut induced throw you have to deal with, but then you have cue ball squirt/deflection you have to deal with. From what I've seen the vast majority of top players will tend to hit that shot with outside english that is intended to be gearing or close to it, and the softer the shot has to be hit and/or the further from the pocket the object ball is, the more they tend to lean that way. I also tend to use outside english on this shot the vast majority of the time if positional needs equally allow for it.
It depends on so many things (a couple of the many are mentioned in the next paragraph), but in general on that shot I would rank the choices in this order of ideal:
1. Outside english at a slower to moderate pace.
2. Rolling cue ball with no side spin and a faster pace.
3 and 4 is close to a tie between rolling cue ball at a slow pace, or outside english at a fast pace, and with even smaller differences yet making the difference on best choice here between these two choices.
5. Inside english wasn't one of the options you presented, but it would be least ideal if positional needs don't require it.
Whether the object ball is coming more from center table or more from closer to down the rail makes a difference, the object ball distance from the pocket makes a difference, the cue ball distance from the object ball makes a difference, just how dirty the balls are makes a difference, and a whole bunch of other nuances make a difference and will often be what tilts things more one way or another on which choice is best in any particular instance, but those are some general "more often than not" guidelines in my opinion.
