It's pretty much all the same stuff.

The main thing is you aren't ever going to get reliable/total command denial out of it, but that doesn't necessarily mean it's trash -- it's true of most of the lagging skills in the game to varying degrees.

The art to it is more in knowing when one or two shield bashes at the right time will take advantage of someone who's overextended themselves a little too much, especially given that as a shield paladin there probably aren't as many characters you can straight out-melee as with some of the bash characters.