While we routinely perform the high knee/running A drill during power speed (3x or 4x/week) I never have the knees come higher than the athletes ability to maintain complete extension at the support knee.
Regarding the ‘knee through’ cue during actual sprinting, I make sure that my athletes know that I’m not cuing high knees as this will often cause the trunk and/or hips to drop.
The knee through, is literal, in that I simply want them to think about punching the knees forward