I follow the USGS earthquake website daily. And I can say that his predictions, are a pretty safe bet, as the levels he is predicting are fairly common events in that area The only one, I have to doubt is the last one for the PNW... Lately there has been an abnormal amount of activity, just below Monterey, and an unusual amount of "less than normal" activity North of the bay. That leads me to believe that something is stuck, and it does seem reasonable. (to a point), that a bigger than normal earthquake could be anticipated North of Monterey up to the Oregon Border, based solely on the lack of movement North of the bay area.
That being said... If it was that easy, I could be rich! Just me 2 cents worth. I wouldn't consider a predicted eathquake to be any reletive indication of tides. Of course unless it's a sunami, in that case I predict lower than average tides, followed by higher than normal tides, in that order. Maybe you can go down to the beach and keep an eye out for us ;-) (Just joking of course. That would be very dangerous.)