I disagree. When Rel posted his story based milestone house rule,
"Milestones - There are few mechanics in 4e that I find less flavorful than the "fight two encounters, get a Milestone" bit. But after consideration, I determined that what I needed to do is to simply turn Milestones into, well, milestones. In other words, have something meaningful actually take place. And it doesn't have to be after the encounter either. It can be smack dab in the middle of the battle.
If the PC's interrupt the Evil Wizards in the middle of their Ritual, that's a Milestone. If they maneuver past the Evil Cleric's minions and blow out the Dark Candles that have desecrated the Altar of Pelor, that's a Milestone. When they slay the Hobgoblin Lietenant who led the attack on their village, that's a Milestone. The PC's should constantly be setting short term goals and even quests. Accomplishing those is significant and earns Milestones (and therefore Action Points). Fighting a random encounter of wolves in the woods does not earn you a Milestone."
Mearls posted the following:
"Interesting trivia bit: at one point, we thought about doing milestones pretty much the way you describe.
We decided against it because we figured that for story-based games, the DM would have a natural progression of scenes, while for a dungeon-based game it might be a pain to label some encounters as important and others as trivial."
So milestones were done the way they were to help support dungeon style play.