I skimmed trough paper, but from what i researched, uv is benefitial when you pump your growth with co2 higher ppm and ppfd…
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This way you can run the AC feed through an A, B, A+B switch or relays to have more control
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The paper you linked and your quote make reference to the only study to find these effects; this new paper you linked didn’t actually study effects of UV on cannabis. The study they reference is from 1987 and has never been reproduced, and it has some serious shortcomings compared to modern plant biology studies.
The 1987 study didn’t have good controls because of the lack of technology back then, and since then no other study has found similar results. It’s not much evidence on which to conclude that UV = more cannabinoids or terps.
Plant biologists think spectrum can likely be manipulated to impact cannabnoids and terps and many other plant chemicals, but, while spectrum has conclusively been proven to control morphology (plant shape), there’s no current research proving that spectrum can manipulate terps or cannabinoids. The videos I linked a week or two ago in this thread have PhD researchers and plant biologists stating exactly that.
All this means it’s fertile ground for future research, but don’t draw any conclusions just yet. 
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Sorry, i should have red that before posting, im at work so i cant focus much… Too bad there isnt any good info on it… I know about oldie on ICMag recommending them, and about papers on other plants which produce oils, but no cannabis…
@ReikoX @Gpaw huh, I would think that if you switched on/off some strips (not all at the same time necessarily) on the dc side it would just draw more or less current?
How would that be bad for the strips or the driver?
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The constant current circuit in the driver cannot handle that situation and may lead to runaway current. That would be bad for both the driver and the strips.
It really is just easier to run two drivers. They aren’t that expensive…
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@ReikoX I know, but I did get a hlg-185h-20ab and I will likely be going for multiple small/micro boxes which will use like a third of the power so it would be nice to make use of it.
Do you know if something can be added to make it work like a resistor, transistor etc?
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Not with that driver, no I don’t know how to do what you want.
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You do that all the current from those strips gets diverted to the ones with power to them, de-power half the strips the other half gets double the current. Don’t try and reinvent or change it if you don’t actually realize how it works.
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Haha I will definitely admit I don’t fully know how it works… for instance, I thought that basically the driver has a certain amount of current supply and the LEDs just sort of take what they want according to the volts supplied?
Is there a different driver that would?
Aren’t there light controllers or something, would they help make that work?
They exist, are less efficient, are more expensive, and require a lot more electrical knowledge. It’s cheaper, easier, and more efficient to use multiple smaller drivers, period.
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I believe also there is still somewhat of an inrush current, in other words as soon as you plug it in the current actually exceeds the rated current for a fraction of a second can’t remember if this applies here but it definitely does in other inductive loads It can reach levels in excess of three times rated current. 
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electrician 
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When I think about automating my grow? Its a bit of an investment? At this point? I would listen to @ReikoX ? The past 2 lights I built, thought the driver would be the most expensive part. Nope, it was the know how, and the parts. OG reassured me of the know how. I can plug and play, all day. @Mr.Sparkle, @ReikoX, have answered many other members questions, made my builds happen… along with questions from all of the members here. Shout out to @Baltimore, your inquries have made me rethink future “grow enviroments”.
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Definitely easier, but I’m not so sure about the cheaper aspect of it, altho I don’t know how expensive those other drivers and possible controllers get…
As I’m sure you know and stated here by others already, in some instances it can be cheaper to go with fewer bigger drivers than many more smaller drivers (with @Gpaw exception with what he found in his driver search)…
Which I guess brings me to another question, does anyone know which specific model hlg/XLG that is the cheapest per watt?
100% that’s why I mention them and ask them because I know they know what’s up…
I guess I’m just trying to see what options there might be, not trying to question what they do really
Actually decide on your space first then then determine how much light you want in the space and add 10% and pick a driver that matches that or is close.
… current efficiencies and such 30w/sqft-40w/sqft is a good range, the lower amounts you should run the lights closer, higher amounts you can run them further away so long as you have the height to do so.
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I’ve already been down this road, I posted about it previously including a cost analysis.
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Man yeah it does look like you went down this road but maybe slightly differently?
I def wish I had certified electrical engineering skills…
@Mr.Sparkle I hear that about the spaces…
Probably going small, and did get a driver with more than I need to give me room to expand later if I want, but was hoping that I could use that one driver for multiple spaces with their independent control, and not in too of an expensive way…
I can hope and ask, I guess I can use that for multiple spaces and then just run those particle spaces the same way and get smaller drivers for independent control for the other spaces, but yeah it would be nice