Anyone who has watched kids playing knows perfectly well that kids can pretend and have as much fun (or almost certainly much more) than if they think it is real. "Let's play house; you be the daddy and I'll be the mommy", or "this stick is my gun, and that one is yours -- bang! you're dead", or "let's play Narnia -- I get to be Lucy!". On the other hand, what about the "real" things? "You ARE a piano player -- now for the last time, go do your practice", or "you're not playing house, you ARE a member of this household, now go clean your room (or "go mow the grass" or whatever)"
Is there any connection between enjoyment and belief or pretending? Pretty much yes, except that it would seem to be the exact reverse of what might lead a parent to "teach" their child to "believe" in Santa. The kids love pretending probably precisely because they know it can end when they want, but they generally quickly learn to hate the "real life" roles they are made to play because that involves "real" consequences that they can't control yet (or perhaps never will be able to).
So we always "pretended" with our son about Santa in the same way that we pretended to hide and seek or pretended to have war with water balloons or pretended to go scuba diving in the bathtub or whatever else. Seems to have worked well with no traumatic revelations about non-existence to be faced somewhere down the road -- kids (and adults who haven't forgotten how) can get fully into the act of pretending and still know how to come out of it back into the "real" world, and know the difference. Lewis even talks about this process of playing or pretending somewhere (can't look it up at the moment) as a primary way that they learn and mature in the world.
So I would say that both sorts of parents, ie, those who teach absolute belief in Santa because they want the child to experience some kind of ultimate fantasy joy in their childhood, and those who "would never subject their children to a lie like Santa" because they want them to experience the "real world", are falling into the same error about who children are and what they can handle.
Let children pretend and let them know they are pretending -- they are pretty good at doing both at the same time. (I suspect Chesterton would probably say something along these lines, though of course better and more delightfully paradoxical -- I suppose one could say he would be more childlike about it?
)
--Stanley
…on a night of rain Frodo smelled a sweet fragrance on the air and heard the sound of singing that came over the water. And then it seemed to him that as in his dream in the house of Bombadil, the grey rain-curtain turned all to silver glass and was rolled back, and he beheld white shores and beyond them a fair green country under a swift sunrise.