On a damp and dreary morning back in early January, long before the winter of 2015 unleashed its 100 inches of snow on the region, Joni and I made a trip out to Hopkinton and ran back, covering the first 14 miles (me) or 16 miles (Joni) of the Boston Marathon course. For Joni, it was a chance to see the early sections of the route she’ll be running in her first Boston on April 20th. For me, it was a chance to re-acquaint myself with a course I haven’t run for over a decade.

I learned two important things that day. First, Joni has become really fast! After a few easy miles, the pace began to drop. By the time we hit Natick, Joni was cruising along at just over seven-minute mile pace and I was hanging on for dear life. I made it as far as Wellesley High School before giving up, but she continued on for another two miles, looking entirely untroubled.

The other think I learned that day is that the roads that comprise the Boston Marathon course are a series of traps for those who do not bother to run tangents. As we ran, we measured the impact of not following the shortest path by comparing splits from Joni’s GPS, which has always been quite accurate when measured on known courses, with splits taken at the mile markers on the road. Because we kept to the left side of the road as we made our way through Ashland, Framingham, and Natick, we knew we were running extra distance, but the magnitude of the effect was surprising to both of us. By the time we reached the half-marathon marker in Wellesley, we had run nearly a quarter-mile further than 13.1 miles.

Now, Joni has been telling me for years that most runners don’t realize how much extra distance they are running by not taking the shortest path, and here was a powerful demonstration. It’s true that the Boston course is particularly snake-y, but in theory, any course with turns presents the same sort of challenge. But Boston is particularly problematic because the crowds are so thick that it’s quite impractical to run the shortest distance. As a result, those following the road will end up running quite a bit longer than the standard marathon distance.

(For a concise essay on the subject of running tangents, see http://www.slowtwitch.com/Training/Running/Math_of_Tangents_1257.html.)

I thought back to that day in January yesterday. On Saturday, Joni competed in the Rock and Roll Half Marathon in Washington D.C. and ran 1:27:25, a PR and two minutes faster than she ran at the same race last year. And on Sunday, I witnessed blatant crimes against tangents while running the New Bedford Half Marathon, which took me 1:28:30 and gave me the second-fastest half marathon time in the family for the weekend.

As it always is, New Bedford was windy. Specifically, from Mile 9 to Mile 12 or so, with mental and physical fatigue peaking, there was a brisk headwind that made life miserable. Naturally, in those conditions the runners were all trying to draft on each other to obtain some small relief from the wind (never mind that at our slow pace, there was hardly any benefit to drafting anyway). But what was absurd was that runners were so intent on drafting that they would follow the runner in front of them regardless of whether he or she was sticking to the middle of the road. So instead of running the shortest distance, wind be damned, runners were adding meters to their races at every sweep of the road.

Is it herd mentality? As I conscientiously ran the tangents, I found myself alone near the side of the road while a huge pack ran in close formation following the center line. My determination to run the tangents marked me as a misanthrope.

And yet, why run the extra distance other than blind peer pressure? Why take the longer road, when the shorter one is right there in front of you. It’s funny that when I run tangents, I can’t quite shake the feeling that I’m cheating a little bit, even though I know that I’m running the course the way it was measured (if it’s a certified course).

Here’s a final vignette from New Bedford that puts this tangent about tangents in perspective. As I was suffering through a rough patch around Mile 10, I noticed a woman running about 30 meters in front of me. Apparently, her kids had come out to see her run by this godforsaken stretch of the course and had stationed themselves on opposite sides of the wide boulevard. She gave a shout of delight, stopped and ran to one side of the road to give one child a hug, and then turned and headed straight across the road (at 90 degrees to the direction of the race) to give the other child an equal hug. She then continued running, full of joy and free of stress. Though I ran the tangents with miserly attention to detail, this happy Mom pulled away and probably finished her extra-long run with a broad smile on her face, having at least gotten something valuable from going the extra distance.