If you were a fighter 4, and your wizard friend started encouraging your interest in magic, would you take a level of wizard before getting that "precious" extra attack from fighter 5?
Sure, if that's what felt best for the story I was trying to create with that character.
Do you feel like you *need* that extra attack before you would consider broadening your horizons resulting from story development?
Certainly not. Letting mechanics get in the way of a good story is, in my experience, the fastest way to a bored table.
To me, the obvious underlying impetus seems to be one of make it through each adventuring day.
I very much agree. If Bob the Fighter can start casting
light, the whole adventure changes. He no longer has to carry torches, freeing up room in his basic load. If he can start casting
fire bolt, he has a ranged attack that is arguably better than the crossbow he was using, and guess what? Less gear to carry!
Even being able to use a weak cantrip to summon a flame to light his smokes makes his daily life easier. And since most soldiers, across the multiverse, are very much interested in things which make their lives in the boonies less stressful, it makes perfect sense to think that he'd go for the Zippo before spending more time on the rifle range, even if it meant he'd miss out on learning how to be an expert sniper until the next course started in six months.
But to me this question depends more on the table than the edition. Gritty, high-combat, "dark" and "horror" tables are not good places to build interesting but less-functional characters and IMO, in-world you would be hard pressed to make a good argument for a jack-of-nothing. If your life is a constant battle for survival, you will build for survival and power and explore interesting character options later.
In a lighter-fare game of world-exploring, tomb robbing or otherwise low-combat, low-grit, fun-fantasy I think players are more likely to consider non-optimized options as viable because they know that missing out on a powerful class feature is not going to break their ability to partake in the game. In-world too, characters could make a better argument for taking such options, as their mere existence is far less brutal.
I dunno.
One of the stories this discussion brings vividly to mind is the 1999 "The Mummy," starring Brendan Fraser. In that movie, Rick O'Connell is optimized to survive in the way we're discussing. Evie is also optimized, but more to the "sage" or "scholar" side of things; she grows somewhat used to the adventuring life over the course of the story, though she never becomes the adventurer Rick is.
And then there's Jonathan. If ever there was a cliché, non-optimized character in a party, it's Jonathan. He's utterly
useless as an adventurer. Yet he manages to survive, and at least once he saves the day.
My point is, without Jonathan the story would suck.
SUCK. If the party consisted of all rugged O'Connell types, all theoretically optimized to survive the adventuring environment, they'd never have made it 20 minutes into the film. They'd have been stymied by the first puzzle which required something more than combat aptitude.
Jonathan requires saving. He also brings a certain amusement and flair to the thing. He's the damsel in distress as well as the jester. All of which builds tension, builds drama, builds a better, more interesting
story. And isn't that what we're supposed to be about when we're gathered around a table, eating horrible-for-us snack foods and rolling dice?
Further, there'd be precious little of the tension which characters with different foci and goals provide. You'd have "Predator," which is a bloody awful story: All the characters are carbon copies, combat-optimized in ever-so-slightly different ways. The only drama, the only tension is the question of who dies next, and in what grisly way. I think that's what shidaku's first paragraph describes, and I can think of nothing less interesting to play. Of course, that's just my opinion.
If that's your preferred play style, go for it.
That's why I agree with shidaku's assessment that we're discussing a style-of-play thing more than an edition or game-dependent thing.
Cheers,
Bob
www.r-p-davis.com