How to choose the right mash temp?

I'm putting together a recipe for an AG English Pale Ale that I want to be on the dry/crisp side. The recipe will include some rye, oats and wheat and BeerSmith is predicting OG 1.047, FG 1.012, IBU 28. I am planning to use WLP007 (Whitbread Dry) which is described as having high attenuation, giving me the dry finish I am looking for.

My question is how do I choose my mash temperature (single infusion)? Do I keep the temp low to match the dry quality I am after, perhaps 151-ish, or would that risk overdoing it with a high attenuating yeast? I don't want a VERY dry or thin beer, just something balanced and crisp. Should I counter the high attenuation by using a higher mash temp like 154+, or does that defeat the object of using this yeast?

I'm not sure how to balance these factors, so any guidance is much appreciated. Thanks!

Many things can affect attenuation. Changing one parameter by a small amount will only change your attenuation by a point or two. I think 151°F would be fine.

But you have to consider your other factors that affect attenuation. If you normally get good attenuation, then 151°F is probably OK to get you to 1.010 to 1.012. If normally you get mediocre attenuation (aeration technique, pitch rate, etc.), you might consider going down to 1.050. In any case, no single infusion mash should be below 149°F.