Premature denomalization is expensive complexity. Denormalization is a great tool, maybe an under-used tool. But you should wait until there are hot paths before using it.
I agree. To be clear I'm not suggesting anyone start denormalizing everything. I'm saying if you're fortunate enough to be on a green project, you should design the schema around the access patterns which will surely be "denomarlized." as opposed to designing a normalized schema and designing your access patterns around those.
