On Salting Hamburgers: Before or After?

Steven Raichlen in BBQ Bible says to form patties & then season before going on grill. This guy has never steered me wrong.

For grilling, I salt just before the patties hit the grill. But for cooking them on the stove, I do what my mother always did - scatter some kosher salt in a very hot skillet (not directly on the meat) before the patty hits the pan. It seasons the meat, and also creates a tasty outer crust.

Kenji Alt tested exactly this question a few years ago and found that presalted burgers come out significantly denser and tougher. Tthe salt dissolves proteins in the meat, which then bind together in long strands that produce a tougher patty--basically the meat sticks to itself. The same thing happens in sausages, where the meat is salted throughout beforehand, but in sausages a certain compactness is a desirable quality. In burgers, not so much.

http://aht.seriouseats.com/archives/2009/12/the-burger-lab-salting-ground-beef.html

Salt will draw moisture out of uncooked meat. Years ago I adopted the (healthier) method of not using salt in the prep of any meal and "top dressing" the product on the plate just before service with a high quality sea salt. No guests have noticed or complained. This allows you to get the taste benefit of salt without pushing the daily recommended top-end limit the Dr's state. Lowering the use of salt increases your health.

There's no hard answer here. I put Worcester sauce a touch of salt in my burger mix.
If I'm grinding my own meat (usually a leftover strip stake or something like that). I treat it more like steak, salting on outside after forming and resting 45min in the 'fridge.

With steaks the rule is to salt on the outside and rest 45 mins before grilling. This allows the salt to season, extract moisture..But wait! if you grill a steak 15 mins after salting, all the moisture is on the top.
At 45 mins magic happens and the salt and juices go back into the steak. (think of it a dry brine).

For burgers. I mix it all together for store bought grinds...and give it long rest chilled---with wax paper between burger.

Pull the ground beef (or whatever) to room temp an hour before shaping. Shape, salt both sides, cover with plastic, and let sit @ room temp for 1 hour before grilling. ALTERNATIVELY, preheat oven to 250 degrees. Shape, and immediately before grilling, salt the top side. Turn that side down. Grill until 1/4" done through on the down side. Salt on the top side and immediately turn over. Grill until 1/4" done through on that side. Remove to a baking sheet and set in oven until desired degree of doneness. When you poke the burgers and they feel somewhat tender, they're likely medium-rare. A bit spongy, and they're medium. More firm, they're beyond help and you should slather with ketchup.

I've always formed the patties, then salted. But, come to think of it, I don't really know the science of why!