Is this strain/pheno-related if one wants to be 100% accurate?
No, I'd say as a general rule of thumb.
You still need to read your girl and how she is reacting.
In the veg stage, You have your light exposure set correctly, are watering properly and your environment is stable. So you make your adjustments so your VPD is in the recommended range. With everything set correctly, your girls begin to pray.
Maybe others can back me up here, but I have observed that the higher the VPD is the harder your plant prays or more sharp angle of the leaves.
I make my adjustments so that the angle is not so steep.
It's kinda easy if you grow Monocultural, but most of us don't, so ya gotta make a bit of a compromise between your girls. It's subjective either way you go but you're fine as long as you stay within those parameters and what you see that your girls like.
I think also if you push your VPD too hard, you open yourself up to nutrient issues Increase in percentage of likelihood of It occurring if your soil l is not exactly 100% spot on. And you can get to the point where the stoma was actually close off .
Being observant is very key I think.
You have to be observant in pretty much everything you do in the damn indoor grow......................................... Ohh I'm not going down that damn rabbit hole right now!!