My vet is relatively young and therefore, recently graduated, plus he has taken continuing classes on dog's skin issues as so many are having problems lately. He is adamant about a dog being bathed no oftener than every three weeks. Drove me crazy when Moira was a smelly dog. Now that her health has improved - she was a starved stray - she has very little odor and hasn't a bath since Oct 9 - just brushing.
Fabric sheets? Not here. Too many chemicals dogs don't need.
Dish detergent - only for a skunked dog. Otherwise it strips the skin too much.
Vinegar/water rinse - go for it. Makes a dark dog shine, too.
Rushdoggie, Lily and Moira are 50% raw fed. Makes for a very healthy dog if it fits with the owner.