I agree with you on the hot feed. Noticed burned tips on some early pics. If I get above 1.2 on any of my strains I get clawing and tip burn. I don't know how some growers are running the higher feed levels.
For me I feed light and unless plants show a deficiency I don't mess with it.
One advantage for me with a recirculating system over DTW is I can monitor how much they are using and adjust feed levels as needed each grow.
Yup I learned the hard way