I think part of the problem with conflicting quests has to do with the ones that are multi-part. I mean the ones that become extended when the original condition has been met. If you pick up a quest while doing the first part it may prevent you from doing the second part if it involves the same characters as the second part of the original quest is counted as a new quest received when the first quest is completed. What this means is that any quests picked up before the completion of the in progress quest will have priority on the npc's shared with the second part of the original quest.
Clear as coffee, I'd say and is my impression do not take it for gospel as it may be the other way around.
