Right on FF. This stuff works, and as the link stated, lasts through several washings. As far as I can tell, it is odorless, too. I spray my boots more often, but instructions say not to re-treat clothing too often (6 weeks IIRC).
Recently read a similar thread and someone swore that spraying down from waist down w/a 50-50 mix of clorox and water, then showering would kill both chiggers and ticks. No first hand knowledge on the matter, tho.
There is one good thing about chiggers, however; when they quit itching, it is nearly hunting season again