A lot of that depends on which light you're talking about. The HLG 200 Rspec definitely did not keep the plants short And had a very even par figure over that little 2.3 x 2.3 tent. Very good penetration with that light!
The first grow with HLG DIABLO 650R Didn't really have short girls. Now the next two runs did but, but that was definitely because of the supplemental UVA and the way I was using it.
Maybe it's the R Spec Aspect of the light.
I think that maybe with as powerful as these lights are, it might be more important to strictly follow the PPFD figures for the girls particular stage of life.