I'm currently locked in struggle at work with the creators of a trainwreck of a graph that I'm responsible for maintaining, that smushes a zillion lines together. I've suggested, as someone with a professional knowledge of these things, that a small multiple might get less headscratching at meetings, less time spent trying to decipher the mess, and more time spent considering and acting on the data. But graphs are one of those things that all managers think they are qualified to have an opinion on, so they're like "we want all the values on one graph so we can compare them", oblivious to the fact—observed at those meetings—that they are unable to compare them.
On the other hand, Patrick Ottenhoff at The Electoral map shows two maps of US states: one shows the states with a county named "Lincoln", and the other that shows states with a county named "Lee". Have a look at the two, then see this one, mashed up in a few seconds with Paint Shop Pro and 50% opaque layers.
There's no loss of clarity, and a considerable gain, in my humble opinion, in the ability to keep all the facts under observation without eye movement. (that's why Tufte called them *small* multiples, because large would mean too large a distance for the eye to travel)
By the way, there's also no reason for them to be jpegs. This PNG is 17K, compared to the originals which are over 100K. And yet the PNG loses no detail (ignore the superimposed text :-)
Why line charts are better than area charts - Kaiser Fung (Junkcharts; Principal Analytics Prep) explains why line charts are preferable to area charts, using an example of a Dow Jones index chart.
2 hours ago