TCQ? you mean NCQ?
Nope there is Native Command Queuing and then this newfangled Tagged Command Queuing that areca is using with the 18xx series. and it pays. They even say in the manual that it enables uber speed (not that exact wording) but damnit if they arent right

wow see your busting out the q6600! wow gotta love those ol beasts, i see you have a penchant for old hardware lately, and seems to suit you nicely. Good Job!

EDIT: if they gave points for PCMV you would be crushing