Well, some dudes on here will tell you "why stop at cedar?" They will tell you that you can actually take an old Gumby doll from the 70's and stretch him into one concise gunwale that acts as an integrated inner and outer and only weighs two micro grams. I'm not that guy. I will only use hardwood gunwales, both inner and outer. And I never glue them on either. And I can still crap in the bush without a thunderbox. I'm old school like that.
I agree with NOT glueing them on.
Pros: light, should be able to find long enough boards to not have to scarf, love the look of cedar.
Cons: soft, strong enough to hang seats, thwarts and yoke on???, did I say soft.
How about hardwood inners and cedar outers.
If you're going cedar might as well glue them. I'm always amazed how much a bag of 60 stainless screws weighs.
How about a laminate with a harder wood strip on the outside to take the abuse and the cedar against the hull?
Don't poke the bear Alan. Mem and Yellowcanoe are already bickering like an old married couple in that other thread.
Didn't Alan carbon wrap cedar for some of his gunnels? I remember them being quite strong.