If I find myself guarding a node in CW, I generally wander the platform spamming chilling scream in hopes of slowing any stealthers (I believe it won't completely expose them but does lower stealth level from what I have read). This should make them visible long enough to expose or at least you know you need to call for help.
But yeah, what a waste to have a Jugg tank guarding a node. Much more useful in the middle of the fight. The only thing that makes them a good node guarder is their survivability. Buys time for DPS to respond to the call.