Multigrain Sourdough Buns

My first post!  I keep my bread notes in a cheap notebook stuck to my fridge, but thought a bread blog might work better, and enable me to share my notes.  I am fairly new to bread baking and find some of the posts here rather intimidating.  I took an artisan bread baking course at our local technical college last fall, developed a wild yeast starter during the class, and was off and running with the longer-fermentation methods.  Before the class I had been making all our bread, but  just plain whole wheat sandwich loaves from my own flour, mixed and kneaded and baked all in one morning. 

Although my freeform sourdough loaves always turn out well, I have not had much luck with 100% whole wheat sandwich loaves using the long fermentation methods, even after experimenting with aging my flour.  I would like to learn how to make a 100% whole wheat sandwich loaf that doesn't crumble in the centre.  Until then, I use my old, all-in-one-day method for sandwich loaves and alternate with the partial white flour sourdoughs I learned in my class.

Today I tried to make buns from one of the recipes we learned in the class, a multigrain sourdough.  It was my first time making buns from one of the class recipes.  They turned out great.

Notes on today's buns:

• recipe from NAIT course
• first time trying the dough as buns
• divided dough into 16 pieces and formed as flat hamburger buns
• placed on cookie sheets to rise for 30-40 minutes
• baked on cookie sheets at 400 for 18 minutes, no steam, turning pans halfway through
• buns softened as they cooled
• good size for hamburgers
• flavour fantastic, good texture

(updated to add photo showing crumb)