I think the problem isn't so much how you strike, but what happens after you strike: if you find yourself pulling yourself forward with your knee joints after y

I think the problem isn't so much how you strike, but what happens after you strike: if you find yourself pulling yourself forward with your knee joints after you strike, then that could cause knee injuries (and pulling tends to happen more with heel strikes). The focus should be on pushing yourself forward with the back foot, not worrying so much how your foot lands. I've had long conversations on this topic with a podiatrist, but it's still not certain.....