Exactly this. Shield Swipe is by no means a lackluster ability. Yes, it does not have increase in hate nor does the effect of Pacification work on many bosses. Yet it still hits with hate potency of 420, puts you on a gain of TP (a fact very useful in many fights that take long and require you to keep hitting the boss constantly) and at least to me personally feels like an ability a shield-wielding tank is supposed to have = hit the target in the face with it!
In all honesty, only points of hate that you need are the points that keep the target on you all the time. Mixing a less hate-generating attack that generates TP for you to be used later in the fight where there might come a spot for it (interrupt or the sort, even though this generally is rare while tanking a boss) contributes directly to the tanks possibly most important job: being ready for something that might surprise you somehow.
But to give credit to those who dislike Shield Swipe, I too personally feel that a system where the ability would be off the GCD and with recast timer of for example 6 - 10 seconds wouldn't be bad. It would add interaction to the actions and also serve as special move interrupting ability (which, yes, the pacification actually does), with the same pre-requirement of successfully blocking an attack (which again contributes somewhat to clever use of Bulwark)
-Me