Guys, are you actually reading what Roger said?
It's about momentum. Stride length will take care of itself if you work on all the other things Roger so accurately identified.
Please slow down, read and think your way through this stuff.
Try to discipline yourself against quick fixes. If something is worthwhile, its worth working awhile to achieve.
For those of you in the mid teens, you're also going to grow and gain strength over the next few years. That in itself will create huge dividends, especially if you focus on the correct timing, sequencing and the rest of it.
Read what Roger said again, please!!