A friend of mine did a MFA in Creative Writing before ending up in Architecture, and I believe he told me he had a couple pieces in his entry portfolio. I would keep it short, however an admissions committee is probably a bit more likely to read something than a firm. If you were applying to firms and wanted to include a piece, I'd tell you not to do so.

I would actually write a narrative for the portfolio and base it off of that. Weave all the skills together into one. Good luck!

I also have a B.A. in English and I am including one piece in my portfolio :)

Thanks for getting back to me! I like the idea of writing a narrative that feeds off of the portfolio...I'll have to start drumming up ideas. 

Any thoughts on the use of a few short quotes throughout? 

Thanks!

You should totally do it.  Many schools seek out students who can write well, whether its creative writing, poems, thoughtful essays or just a creative narrative of each of your projects.  Waay too many students these days only focus on design, software and the visual side, creating fancy looking architecture that lack any depth or thought.  Being able to write well and design shows that you can be critical and thoughtful to say the least.  Many respected architects and members in the architectural communities are well known for their writing and ideas in the form of words.  e.g: Rem Koolhaas, Zumthor, Pallasma etc.

Infact, the school I got my undergrad from actually had an entry exam that required us to write a creative response to a text and question we were asked to read and understand in the exam room.

Thanks for encouragement! This was the final piece of my portfolio that I was unsure about.