If you have fun isn't that the point. Ideally games should be a here are the simplified rules so you can have fun fast. Then here are the full rules so you can play a much more complex and fun game. Of course pulling that off is hard.

This is addressed in TFA. In many cases, attempts to create a simplified version of a game just teach bad habits; strategies that work in the simplified game might be not just suboptimal when the full set of options is available, but actively counterproductive.

But I dare say many fans of "heavier" games - especially ones with more of a simulationist bent - would disagree that having fun is sufficient.

Ultimately the fun of a heavy board game comes in having interesting decisions to make and executing your strategy.

So the nuances can really matter. Even if you get the rules right, you don’t realise the importances of something until you play once or twice.

It's iterative.

You're not going to learn a full complex ruleset in one sitting.Having a one page quick start of the game structure, allows you to get a feel for it before coming back for a deep dive.

Your brain has a foundation to build on when you read the ful complex rules - it wont feel like your brain is maxing out at 100%.

Agricola is pretty old. Many of the older euros that were translated to English are shocking. And the way information is conveyed is noticeably worse than a good modern euro.

The original Agricola rulebook is almost completely unusable and the only way to learn how to play back in the day was someone who already knew how to play teaching you - I presume in an unbroken oral tradition all the way back to Uwe Rosenberg.

More recent Agricola rule books are much better.

Agreed, we tried to learn how to play from the book, and then got an existing player to help

In a typical wargame special case rules are numerous, but mostly expected and conforming to familiar design patterns (e.g. entering a map hexagon containing something special with a unit, depending on unit type and state, is going to cost some extra point of movement or end the move completely). So they and can be looked up when needed (e.g. what units can move enough to cross this river this turn?) and promptly forgotten. It is usually enough to study wargame rulebooks just enough to know general procedures and trust the simulation to be unsurprisingly realistic.

I have not encountered a wargame that shipped with two rulebooks in the box, but often the latest rulebook PDF is available as a free download, so when playing a large wargame we often have printed one copy for each player, or at least almost that many. It is always good to have a rulebook within reach.

It was rare, but appreciated. The full-color bound rulebook was almost always better than a PDF printout (though rarely the PDF would be a newer version).

What was the rule you didn't know about?