Glad you've found something that works for your pups
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I've learned not to listen too much to what dogs products people say are the "greatest" cos it's just like people products, what works for some doesn't work for others, and people's view of what looks good often varies significantly from what I think looks good.
Infusium 23 is a great people leave-in conditioner, so not too surprised to hear good results on your yorkie. Did you leave it in or rinse it out? You'll have to let us know how it works with repeated use and if there is any build up. I've used Patene people conditioner on my yorkies for decades with great results, when I've ran out of doggie conditioner.