Frady's premise wrong?
I'm old enough to have seen The Parallax View when it first screened in theaters. It was frustrating at the time, but I think few films, save for maybe Eyes Wide Shut, have expressed a zeitgeist of paranoia & ambiguity quite as well. Answers are simply not forthcoming: e.g. why is Parallax going after both Hammond & the senator on the airliner if they're opponents?
Still, I think Frady's basic assumption, that Parallax was recruiting assassins, was wrong. They were recruiting patsies, fall guys. People with personalities & histories that would make them believable as obsessed lone nutters, but who were also in no way reliable enough to operate as killers. Imagine one of them in custody, is he really going to take the fall & not tell the authorities all about Parallax? The only way an organization such as that can operate is to remain in the shadows.