It's obviously a bunch of machines pointing to 1 worker.
I made some changes and got my 290x cards working, I get 10mh/s x11 and 16mh/s Quark at stock clocks, not too shabby.
it is defintely a number of machines pointing to one btc address ( as noted in the machine list underneath ) ...
but what you described is the way we do it with our farm also ... a number of machines pointing to one worker and mining as one worker ...
btw - what miner do you use to get those rates - and what settings do you use for the miner? ...
nice hashrates

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#crysx