Light spectrum?

I have the OpticLed 650s with 3 dimmers for white red and blue. The directions say go 100% power on all 3 dimmers in flower but I see a lot of people using red light in flower. Any thoughts?

One needs full spectrum to get the most from your plants just red spectrum tends to cause plants/buds to stretch and elongate not desirable
By suggesting one use all during flower also gives you the max amount of light or power the light is capable