If you give your plants enough light, you should at least meet the seed seller's estimates for yield.
It's almost impossible to cause damage to a cannabis plant with an LED grow light. In four years on three cannabis sites, I've only seen it once. It is quite possible to give plants too much light and, if you do, the plant give you a clear indication within about 30 minutes. If that happens, raise the light and inch or two and you should be good.
Insofar as the plant is concerned, there is no reason to increase light levels slowly unless you're near the light saturation point which is roughly 800-1000µmol in ambient CO2, assuming that light is the limiting factor. By about week 5, a cannabis plant has matured to the point where it can process that level of light.
Given a grow that's at, say, 600µmol and is in flower, it's completely reasonable to increase the light levels to 750 and then 900 and then 1k in a few days.
Photosynthesis is an ongoing process and if the plant is getting too much light, it will curl up the edges of the leaves closest to the light. That's called "tacoing" or "canoeing". Another reaction is for the leaves to rotate around the petiole in the same way that a Venetian blind opens and closes.
It does not take days for a plant to adjust to a bump in PPFD. If I had to bump up the PPFD, I'd jump it by 150, check the plant after 30 minutes and, if all's well, check the plant again after 30 minutes and then check it later in the day.
If there's an issue, just raise the light an inch or two or drop the dimmer 10%. It's no big deal if that happens.
I give my plants a bit too much light in early veg I almost ever grow. That happens because I grow in high light (1000µmol by about day 35). When I increase light levels, I'll add, say, 100µmol and then check at 30 and 60 minutes. Sometimes it's too high so I drop back to the previous settings and wait a day or two.
Below is the text from my grow journal for my most recent grow. Note the entry at 9:41 AM. 708µmol was too high so I dropped the PPFD for one plant to 698 and to 634 for the other. This entry is from day 23.
23=day number
3.2=week.day
420PPM (yeh, I use PPM)
60=pH
698 and 634 = PPFD
60 and 55=DLI
Start and End values are runtime for my pH doser.
65 is the water level
I use an Apogee and measure light levels daily (when appropriate)
