Hmmm. I think it loses more Tufte-points for not indicating
"seconds" on the y-axis. I had to scan the nearby text for a
bit before it was clear that things were getting better rather
than worse. The word "seconds" appears only once on the whole
page, and never next to any numbers or column headings.
Hmmm. And while we're at it, the large number of parallel
vertical lines, in my opinion, creates too much visual noise.