no man actually I think that the 600 would give enough saturation to the canopy that the extra light would really just be heat
because the plants wouldn't be able to consume the amount of photons
for a fixture to cover a 4x4 DIY I would say around 12-15 hundo......to cover a cob per sqft...which would be the most efficient.....at around 50 watts....and let me remind you these cobs run about 130lumens per watt which would be about 6500 lumens per sqft or 104,000 lumens per 4x4
but the main difference is the efficiency which means that say a 1K hps puts of 140K lumens but really they are only about at most...gavita.....40% efficient.....which means that 56,000 lumens are hitting the canopy where as the LED is putting down about 58,240 at 56% efficiency spread perfectly to each sqft
the sole reason why HPS talking gpw usually only pull anywhere between .5-1 gpw strain dependent
and the LED is putting down 1.5-2 gpw on average...with specific LED's like Cree and Vero COB fixtures