I think you have under estimated the effect that the USPTO reexamination process had on the ability of TPL to extract money from infringers over the past 3 1/2 years. True the patents were always valid during this time period but the real question was what would the patent look like after reexamination. With the outcome of the patents in question, I believe most companies chose to wait. Their plan to drain the pockets of TPL and PTSC in the meantime appears to have worked pretty well in their favor.