Giving your players lessons on how to play the game by having NPCs play the same game is a bit heavy-handed...
But then again, even the heaviest hands sometimes fail to hit their mark.
Chirrut's look of utter horror is just perfect. I imagine the next scene is him breaking out of the cell shouting about Dexterity modifiers.
In all seriousness though, learning from past mistakes is very helpful for character building! Some builds look great on paper but then don't end up being very fun to play. After some experience, you learn what "balanced" and "unbalanced" look like, what would really be considered a "good" number or a "bad" number etc.
A parallel point to this, is that it's also fun to play a character nothing like your last character. Jump from brawny barbarian to a brainy wizard, or a brash, outdoorsy ranger to a foppish but diplomatic aristocrat. You get to expand your roleplaying, and also get a chance to take on different tasks/roles in the party. No one wants to just be the healer, the crowd controller, lock opener, or the hit-things-guy every time (well... unless you're one of those "I will be an Elf wizard for the rest of my life because they win" people).
A comic called Nerf NOW!! took a look at what highly specialized builds in nature would look like. Things like whether or not it made sense to put a point into eating plants so you weren't stuck as a pure carnivore, or if that point was better spent making you a purely strong fighter. What putting lots of points into intelligence did to the meta. And even the functionality of a max Charisma build.
Pete clearly knows how to make a well-rounded min-maxed character. Even Jim knows some tips and ideas to make a better character.
But the GM... Hasn't this GM learned that if he kills off the characters he has to start the campaign over? (Comic 6 I think? From memory...) [Ed: 9 actually.]
GM: Meanwhile, Cassian: You see several of Kyle's partisans carousing near your cell.
Leevan Tenza: You'll never catch me! I've put every character point into Speed.
Partisan player: Why did you do that?
Leevan Tenza: My last character had every point in Strength and got swallowed by a tortapo.
Partisan GM: You <roll>... fail a Spot check and <roll>... trip over a hidden rock and <roll>... fall flat on your face and <roll>... die.
Leevan Tenza: Damn. In future I'll put all my points in Wisdom so I won't get into fights in the first place.
Chirrut: What the dickens?? This guy has no idea how to make a well-rounded min-maxed character.
Leevan Tenza: Screw this game, I'm leavin'!
Kyle: Hey, Leevan, I've got some great pointers for your next character!