PNW seismic activity and my theory.

So the Pacific Northwest has been having quite a few tremors lately, mainly under the north part of the Olympic Peninsula and the Straits of Juan De Fuca. The seismologists say it is associated with a slow slip deep in the subduction zone. This has been happening every 14 months since the 1990's. Now logically it follows that if you have movement of part of the subducted plate deep down you should have some movement, or at least a corresponding tension build up along the shallower depth along the subduction zone. Since I have not read anything about movement on the Cascadia subduction zone I can only assume the tension has increased by the same amount of energy as released by the past tremors combined and then some. The question now is how much tension can be stored before it overcomes the friction of the two plates and releases all the stored energy in one massive earthquake? How close our we to that number?
I will tell you that when it happens it will be at least an 8.0 moment of magnitude quake, most likely a 9.0 +. If you thought the Japan quake and the Indian Ocean quakes were bad this could surpass them and generate a serious tsunami that will hit the Pacific coast mere minutes after the quake.