I've been having issues with the recently nerfed pyrotech slow talent, Sweltering Heat. It applies the snare/debuff for the first 2 ticks of the cylinder DoT(2sec 30% slow applies per tick) but refreshing the DoT with Flame Burst removes the tick->snare application. A railshot refresh still works though as per the relevant skill tree talent.
Additionally, the tooltip says 2 second slow on application of the cylinder DoT but it's applying a 2 second slow on a per DoT tick basis from first application(4sec total slow).
So yeah, lots on inconsistency and need confirmation.