I noticed you made sure to say "dont let the powder poof in their eyes" when suggesting the Gold Bond or Cornstarch powder to keep dry...I always recommend buying a set of the plastic picnic ketchup / mustard containers. You can get them cheap at Walmart or the dollar store. The pointed tip helps get the powder right in the wrinkle and no where elseWe use Gold Bond a lot in the tail pocket too.
I apply the powder to my fingers and then run my fingers through the folds.