Two late thoughts:
Firstly, since the implication is that, as a head-on tackler, you must no longer go into contact upright, does this mean the end of the choke tackle?
And secondly, instinct tells me that trying to go low to tackle in a head-on situation might easily lead to getting a knee to the head - is that not at least as dangerous as being punched and likely to lead to serious concussion danger for the tackler?
Just wondering!