And obviously as soon as I had written it down, it came to me. Sometimes it just requires an interlocutory (even a silent one) that you need to explain the problem to, to re-organise your thoughts enough that the solution presents itself to you…
Let’s still keep the question with an answer for future me, who’s sure to ask it again…
In the timeline graph, I assign a y value that’s just a number. By setting the same y value to all bars that need to be on the same line, I get the desired behaviour (although obviously those bars can overlap if the data overlaps).
That simple…