Call me crazy but I am pretty sure you're supposed to use dragoon + war for stun, paladin + bard for silence, monks being the "wildcard". FFXIV goes a step further than other MMOs by making certain moves only interruptable by silence, and others by stun, and some by both.
Shield Bash is a luxury, one paladin stopping everything certainly isn't the intended design. Hence why they changed it in 2.1.
