It's more likely that the dean is just not the person who should be writing the grant proposal. Professors whose groups are actively working in the area the grant is for will write a much better proposal. It's also expected that as a professor you are -- to a significant degree -- capable of funding your group.
I'm not even talking about grant writing. I'm talking about things like negotiating licensing agreements for private industry, contract negotiation to make sure publication and graduate students are protected, etc.
