Dimension Line Snap Distances are very usefull tools in our Revit arsenal. Afterall, who enjoys a drawing that has dimension lines all over with unequal distances inbetween them? As Edna Mode says, "It distracts from the now"
The Dimension Line Snap Distance setting can be found in the Type Properties of any dimension. The default snap distance setting is 10mm (Remember that dimensions are annotative objects).
By changing the snap distance to 15mm, the end result is clear.