The roads engineers claim that the King's junction is "very tricky" because of the number of bus routes going through it. (But strangely no mention of it being very tricky due to the huge numbers of cars they're trying to plough through it as well)
If they would just put in a handful of bus gates along the Queen St, Western Approach and Lothian Rd traffic sewers all this traffic and the "problems" trying to accommodate *everything* at the King's would melt away