being a warrior, i will admit that they are undoubtedly the easiest class to play lol. hard to tell between a 2k and a 2400 warrior even >.< i go slam spec, some prefer incite. rotation is rend>cs>ms>op>slam>hs when lots of rage. try and get lambs up before you blow cds if possible. use your fear and try to get focus interrupts on healers ect ect blah blah, intervene scatter shots/blinds/kidneys if possible.. gem str, str/resil, and str/hit. some prefer reforging expertise, some prefer crit. i prefer crit. happy tunneling.
if its against a disc they'll silencing shot before the scatter sometimes so it doesn't get SWD, so that can be an indicator. otherwise yea if you see him running trying to get in your healer's LOS, he's just spamming his focus scatter macro lol. interrupt bar helps as well.