I did this recipe a couple of weeks ago and yes, it's fantastic. The timing is a bit of a pain, as he's very specific, but still worth it.
However, after looking at dozens of recipes for lox, I haven't yet come across any that reference a second brine. Most just use salt and spices in a dry brine, then smoke.
Is it just a flavour issue, or texture? Anyone done a single dry brine only?