Yeah, that's exactly how I work it. Pretty sure that's by the book, too, but I don't have it in front of me.
Weapon ranges are
a key bit of fictional positioning (must... resist... urge... to... flood... thread... with... theory... talk... XD)... well, I'd say they're one of the best/easiest examples of how you can let the fiction lead things.
It actually reminds me of the old story of the gazebo (
http://www.comedycorner.org/90.html)... you can't hurt it with an arrow, even a +3 one, but you could with an axe or fire. Of course, this is more "damage type" then range, but it's really a similar idea. :)
Oh!
But, I don't just have my players roll defy danger right out. I mean, sometimes I do, but that's lazy and against the rules! I try not to.
What I do is, I tell them what's up and ask, like "He's not gonna let you get anywhere near him with that knife, and he's got the reach to prove it. What do you do?". Now, they might duck and weave to get in close (defy danger with dex), they might try to create a distraction or feint (probably defy danger with cha), they might go full bad-ass and be like "Alright, let him stab me. I'll roll to take it in the shoulder, then go right for his throat.". Then they just trade damage, I'd say, and then maybe the player would need to defy danger (maybe with con?) because of, you know, a spear in his shoulder.
Of course, there's all sorts of other things they could do, and that's the point. But, yeah, for the typical case of "Get close and try to avoid the spear.", it's a defy danger with dex. Please note that, unless the enemy has another weapon, the follow up isn't hacking and slashing (since, once the player is close, they can't bring the spear to bear properly), it's just do damage.
- Alex