all plants can be manipulated for increased yield. Even a longer veg period has huge impact on yields.
maybe.."what's the heaviest yielder with no training and only 30 days from seed in the veg, with a 600 watt metal halide covering a 2x2 ebb/flow tray hydro set up, and a 1000 watt hortilux eye hps in over a 2x2 tray also, in the flower room, using Dutch Master Gold nutrients changed weekly, constant temperature of 75f, and lights on c02 1500ppm. no bud boosters or pk and humidity is always at 50%,no pests/ or toxins ever." or something like that.
Other than that, I would say Critical+ is a good yielder, because with the above, they finish in 45 days, allowing extra harvests yearly, and top smoke for most. Heavy duty fruity weighs in, but are mids. I never take less than 4 oz of dry colas from my PlushBerry line, and they veg for 35 days, flower /finish in 60 like clockwork, and is a+ as seen below