Thanks Cala! Cala is another great poster here who really knows stuff!
Yes, do make sure a Growl lands before laying on dps when fighting things 3+ lvls above you.
You tend to see a "resist" in the air above target's head if they resist Growl. If Growl lands, you tend to see a blueish purplish ' ' ' above their heads.
Again, my problem is that I play lock and hunter - and I don't want to confuse you w/ demon stuff. I would go so far as to, on a target 3+ lvls above me, not to shoot a bit until at least one Growl lands. If a Growl or two gets resisted mid-fight, you can easily pull agro, too. If you see Growls missing mid-fight, that might mean its time to not do that Arcane Shot or whatever - or even stop auto-shooting a tad - until target's hurt enough that if it charges you, it is too late for the target - it's dead, anyway.
Of course, Conc Shot, Wing Clips, traps - even FD - we have ways to deal w/ unwanted agro. But watching for taunts/growls to land is often the best, and holding back on our dps til pet gets a tighter hold on agro.
Note, while its fun and thrilling to hunt stuff over your level, some of the best and most efficient gringing is on low yellows and high greens, according to many. In fact, Jame's leveling guides put you on pretty easy-to-kill stuff. I know this can get boring, and the thrill of killing somehting red to you is good - I like doing that, too! But you may want to move to an easier area of STV for yellows and low yellows for "pure grinding" - it tends to go faster - in part because there are fewer deaths and fewer times you have to run, fd, etc. GL!