Plot Points are a way of trying to control the flow of the game and campaign story. I write them out beforehand. Each location has a Risk – an enemy that is triggered when a model in BtB spends an action to Search – and a Reward, some minor item like a healing potion or one shot weapon boost, or morale buff that is only available after they have defeated the Risk.
There are also a couple descriptive sentences about the scene and some clues about some other part of the game mission.
For example, last night the party searched a Border Guard tower near their deployment zone and found recently slain guards, a healing potion, and a map of the area that showed a previously unmarked ford across the river. (The river with an old stone bridge were further away on the table)
The party decided to go for the ford rather than the bridge, which turned out to be a wise move, as the GM (me) had placed a party of Orcs in the trees near the bridge. The greenskins were waiting to ambush the party and had left one orc fighter guarding the ford. As a result, the party dispatched the lone orc guard, crossed the river and fought the ambushers at an advantage.
Bottom line is I'm using ASOBH as the core mechanics for a RPG-lite style game.