So the OD&D format was stuff like KEEP ON THE BORDERLANDS where there was an adventure background, an expected plot flow, and then numbered encounters based on a map with the (then brief) stat-blocks listed with each encounter. This worked back when there werent' so many sub-rule-abilities for each monster don't you think?
Then there were things out there that were entirely fluff, which where it was just freeform, with NPC backgrounds and a story with stats randomly sprinkled in there somewhere. There were side-bars thrown in wherever they seemed to fit in the text. I remember a lot of 2e stuff being this way. The early 2e formatting seems really terrible for game play unless the DM has a photographic memory and just likes highlighting huge blocks of text.
RPGA seems to have pioneered the hybrid format I suppose with the advent of massive numbers of scenarios produced and feedback from DM's regarding formatting. Then they had the Living Greyhawk format where all of the stat blocks went at the END of the scenario, based on Tier (no thanks SRM

. That was by far my LEAST favorite format.
DUNGEON tried the OD&D format, but with "symbols" for different types of encounters at one point as I recall too. Their magazine format had to fit with artistry in most cases. Referencing maps back and forth was always difficult in those types of scenarios.
Now that I think about it, a whole page (or two) in the DUNGEON DELVE format seems pretty DM friendly, but it seems to force the adventure towards being very D&D-Miniatures-Combat-Heavy. I'll
admit, it's definately easier to run, but there has not been (thus far) much plot development capability for this approach. Yes? No?
jh