Wouldn't a sticky thread with links be better than a child board? If one person maintains it with updated links to all new guides, the guides don't even have to be on the same board.
Perhaps. Nevertheless the way it is organized on the Italian board seems easy to find too. If only one sticky acts as an index, and is maintained by a specific user, then he/she can sort of "supervise" the guide quality/utility before adding it to the sticky post. On the other hand, the Italian solution allows for a decentralized approach, where all guides are concentrated under one child board. The downside to this is what I mentioned previously: not all guides there are good really, but anyone can add a guide to something there.
I guess that, from a quality point of view, the single user managed sticky thread would be better, but from the freedom to add a guide point of view, then the latter option is fine. One option is like an index, and the other like a directory.