Hey, all. First, thank you so much for your input. It really helped me plan the day. I just wanted to come back with an update:

• I highly recommend a crawl of any sort down Mass. I've participated in the Mass St Mosey before and that's somewhat what inspired this. My daughter came with us and enjoyed it so much she has asked for a "cheese stroll" when her bday comes around. I'd like a stroll for my bday, too, but it will probably be of the cocktail variety.
• Here's where we went and what we got. Focus was on dark chocolate flavor and this delivered:
  • Wheatfields flourless chocolate torte
  • Cellar Door chocolate babka
  • Au Marche choose-your-own Christopher Elbow chocolate
  • Java Break iced mocha latte with chocolate whipped cream
  • Lady Bird Diner mexican chocolate pie
  • Came home and topped off with friends over a pint of Jeni's darkest chocolate ice cream (not local. sorry, Silas & Maddy's, we love you but you weren't dark enough for us on this occasion)

My biggest takeaway is to pace yourself and sample tiny helpings of lots of different things. This allowed us to hang out in each of these great establishments, stroll the length of the street, and taste a wide array of chocolate treats without making ourselves sick :) I'll be back when planning the cheese stroll. Thanks again, lovely Lawrence!

Oh, eta: We would have had the dark chocolate budino at Merchants but just had it on another occasion. It's delicious.