yep would be the right way of doing it i fully agree...
my light only goes 40-60-80-100% (250w-380w-520w-645w), and no external controler here, i could play with height adjustments but the test was to leave it maxed out and play with dimming this run, if i started 60% until end of week 4 i think all would be just fine, will do that next time.
this ones got 80% at 1.2m from canopy first 2 weeks got fried, than 2 weeks back to 60%, didn't recovered too much but didn't got worse either and were slowly flowering, after raising back to 80% the flowering increased speed significantly, they are still at 75cm PWRs and 90cm CDs from the light tho, i never moved the light height (light is at 1.5m/5feet from the media/pots).