I, too, see no reason for someone not to replay or read the spoilers in advance, if they so choose.
The main goal here is
learning. As long that goal is served, then the group is benefiting.
I, myself, try not to read the spoilers in advance, but it means being careful about which of those messages from "Civilization Fanatics' Forums" to read and which not to read, since spoiler tags don't show up in the email messages. This round, I played in one straight session, but in a previous cookbook I reloaded in one turnset more times than there were turns!
As long as people aren't being extremely abusive, then I don't mind people choosing the level of reloading that they want to use, especially if they share their results, such as "I tried Work Boat first and Worker first, and I think that X strategy gives you a faster initial development." Just try to
avoid doing things like:
a) Replaying and choosing a
settling location that no one could have come up with without map knowledge
OR
b) Overly abusing knowledge of Resource locations, such as
settling next to the
far-away Copper in our game, knowing where it was from a previous session or reading a spoiler,
without even bothering to learn
Bronze Working first
OR
c)
Reloading battle results. I don't care if you reload five turns back and decide not to start the war at all, but once the war starts, please just play it out. You'll learn far, far better that way and reloading battle results DOES defeat the purpose of learning how to successfully fight a war