1.5 gram x 2000w roughly (280,000 lumen)
is 90 oz from 10 plants
that i do not think is possible
to get 1.5 grams per watt would require exceptional management of space available
to fit that much/cola bud in that amount of space that 2000w of footprint of light can cover is a huge achievement .. many may claim this but as we know, many people claim many things
9 oz per plant each plant getting an average of 28,000 lumen obviously subject to distance from the lamp
as a side note 3 x 600 w hps at 95,000 lumen each would give you slightly more light (285,000 lumen) using less wattage (200w), with the advantage of giving you better spread across your crop .. why did you not consider this .. ?
now to break this down to get 9 oz from 1 plant that is 6ft+ tall with only an average of 28,000 lumens max available sounds ludicrous to me
having grown many larger plants myself i am aware of how much light they need
to fully cover them and produce nice tight dense bud
10 plants over 6ft tall only receiving this amount of light are not being grown to their full potential in my opinion
whatever yield you get good luck i hope it all turns out great for you