>>3438177Part of the benefit is that it is an anti septic and letting it rest in your mouth helps there. And that nothing will be as well crushed unless you do it with your own teeth.
Also while water helps swallowing it, many substances from the garlic oxidize very rapidly. Alicin for instance oxidizes in 5 mins after you cut it or crush it, water may or may not accelerate the process, but olive oil or any other acid preserves many of its properties so you get the full benefits. They just go well together. I think it was Walmart or some other American distributor that sold garlic pulp preserved in acetic acid from vinegar. Works by the same principle.
Anyways I do it because it's easier, tastes it better and olive oil is very good for you too. Didn't even notice I was chewing garlic and will be able to do it again with no complications on a regular basis.