Today I made Eric's Fav. Rye (from TFL) and all appeared to go well --- until I pulled the loaves out of the oven and sighed at the pasty-looking, not-at-all-brown crust. It was steamed for the first 10 minutes at 370, then 30 additional minutes at 370 (per the recipe).
A couple of weeks ago I had the same result with an experimental sourdough I made (Eric's is also sourdough-based with a yeast kicker).
I very rarely have this happen with a sandwich loaf, but maybe once or twice in several years.