Vertical Bulb - I think you could get 3 lbs with a stadium style grow. It's simple math. Build shelving around the room and calculate how many ounces you will get from each plant. 3 lbs is 48 ounces, so if you can get 50 plants in there about 16 inches tall, you should be able to pull atleast an ounce each. Hang your 1000w vertically without a fixture or with a cool tube....You will get amazing results with 1 6x6 tent.
You could also SOG to hit 3 per light. Purchase a 4x4 tray for a hundred bucks, create drainage, put a 200 gallon smart pot in the tray, then fill the smart pot with Roots 707 soil. This is a soil bed. I would place 144 clones in that tent, veg for 1 week then flip to 12/12. No training and you will get 10-14 grams per plant, easily.
Just calculate your canopy surface area, then estimate the yield on a per plant basis...I've never done it, but I'm sure you could easily hit 3.