Graphically Displaying Three Synoptic Gospel Data

Yesterday I offered why prefer to use rectangular shapes when displaying synoptic data in a Venn diagram. I have created several instances of these examples using verses, sentences and even words as data points. Using the Aland Synopsis Index as a quick and dirty (very dirty) easily accessible set of data, displaying each pair of synoptic gospels could look like this:

However, the superiority of rectangular shapes really shines when combining all three. I did not take the time to gather the specific numbers (yet maybe), but this is approximately what a resulting Venn diagram looks like compairing all three gospels.

Again, the proportions are very accessible upon examination. You can see that Unique Luke is what proportion larger than unique Matthew, and how it relates to what Luke shares with Mark, etc.
It is only when you add a fourth source that you need to create it as a polygon. And with that... the result is still a series of variously overlapping rectangles. Visually comparing rectangles is much more helpful for proportional comparison than common circles and ovals of Venn diagrams.

Note that there are still advantages for keeping the three separate pairs overlap comparison side by side, as three discreet diagrams.