I have been washing my harvests for years with fantastic success. The process I follow is not my own, but rather a grower on 420mag named DocBud, the inventor of hibrix I think. Anyways, I made a video a few years back the explains everything and there's a couple hundred page thread on 420 called "Bud Washing" that has more details and obviously a fuck ton of testimonials.
Basically though, the main wash consists of 5 gallons luke warm tap water mixed with a cup of baking soda and a cup of lemon concentrate, then a hot and a cold rinse bucket. In the video, I used 5 gal pails, I now use totes on a table. The wash dissolves any foliar spray residues, insect corpses, insect shit, out body hair and skin particles and other debris never seen, but definitely smoked (yuk). I encourage all new to this process to first try a sample wash so that you can compare how both washed and unwashed smoke tastes. Once you smoke washed bud, you'll never again want to smoke unwashed bud.
Edit - The H2O2 stage is only used mold is a concern. Omit this stage otherwise because bud washed with H2O2 will dry quicker than bud not washed with H2O2 and might screw up the cure as well.