I like C.S. Lewis's writings too. But I'm not Protestant (or Catholic either, for that matter). The reformers didn't reform enough, and even practiced catholic-like punishment of "heretics" with whom they disagreed. I'm averse to "come together, right now, over me" theology.... unless it comes together around the cross and resurrection of Jesus.
The reason they say "ignorance is bliss," I think, is because the ignorant person doesn't know how igorant he is and is therefore spared of the humiliation.