You may need to have a talk with Bruno.

He debated me on Twitter earlier this year as to whether a drier track always meant a faster track. I directed him here to read up the study and then never heard back from him.

Certainly there are many occasions where drier does equal faster, but you cant possibly say that is always true and you need look no further than the beach for that evidence.

He seemed to be saying that the less moisture there is in the soil the more hard-packed it becomes, and the blog that is linked above leads me to believe he still thinks that way. You have to have moisture to hard-pack soil. Dirt that is too dry becomes loose, not sure how there could possibly be any debate about that.