There are many good points on both sides of this issue. Here's my take.
My spouse and I are the parents and we will look out for the best OVERALL interest of our daughter period. Not just her soccer interest, not just her education interest. Note that I am trying to downplay whatever personal interest we may have. This OVERALL interest is a function of the child and each child is different. Therefore, there is no one right or best answer to the question at hand in this thread. And while I love to have the USA as a soccer power to cheer for, we are not going to make decisions along with my daughter for the development of the sport. That is not in her best interest.
There are only a few who have the physical talent, innate thinking, and desire to compete at the level neccesary to make a national team. For them, I think the answer is clear ... forget school ball, or at least make it just a hobby or mental/social release if able to. The reality is that with the direction US Youth Soccer and ECNL are taking things, school ball will eventually not be an option for those desiring to play at the highest levels of youth soccer. The rest of the world does not develop players through school systems, it's through clubs. Not saying it's right or wrong, that's just the way it is.
My daughter will compete at the next level but is no where near a national player. Could she be? She's fast, intelligent, hard working, competitive .... but the simple thing is she doesn't really want to do what it takes to be a national or even regional player. Don't take this as laziness, not that at all, it just her desire to do other things, and do them well, makes it impossible. That's her decision and I will support her as such as being in her best overall interest.
I shall stop now at the risk of rambling on and losing my overall point. It's up to us parents to determine what is in the best overall interest of our daughters, and to guide and advise them towards that end. Soccer is like all other aspects of life; there are many directions to take and many decisions to be made. While it's hard, at least our daughters have options, unlike many in the rest of the world. I believe I know what outcome is best for my daughter (keeping both school ball and club ball in separate seasons) but I also know that may not be best for someone else's daughter.