This may seem a very strange topic, coming from a running technique coach.
Have I gone stark raving mad on a Monday morning?
No, it is my belief that running technique has a 'middle zone' when it comes to analysis. More common is to do too little, but you can also do too much.
I have never, ever told or suggested to an athlete how their foot should strike the ground.
I just don't think its necessary.
The footstrike is a function of posture, particularly the hips/pelvic position, coupled with cadence and its impact on knee drive.
If you are upright and not leaning forward, or collapsed at the pelvis, your cadence is quick (thanks to a quick arm movement) and you have a snappy knee drive (where you are driving the knee not striding forward) then you are hard pressed to land anywhere but beneath your body.
To land anywhere else would quickly imbalance you and your body would correct.
Telling someone how to strike the ground is always going to end in disaster. If you tell them to land on their forefoot they will reach forward and land in front of the body on their toes. A few weeks later they will have a good going Achilles injury.
I was told in the distant past to heel strike, this caused me to reach forward with my heal and land in front of the body, causing a massive brake.
Where you land is far more important than the details of how you land, in terms of which bit of the foot lands first. How you use the energy from the impact, now that's a different story!
So,stop worrying too much about how you land. Work on your posture (see articles on posture) and you cadence/knee drive and the rest will take care of itself.