Lengths of tangos in my collection, by Traditional and Nuevo, including milonga and vals:
Ghost, a frequent commenter on this blog, observed to me that when he was last downstairs at Negracha, the lane system was much more noticeable than usual.
He put it down to there being a live band, who were playing short songs, so that "the log-jam effect was for a significantly smaller portion of the time". There were also fewer people dancing than usual, and they may well have been the more competent or experienced than average, and more able and motivated to create lanes, but I think the observation about song length is quite interesting.
Does the length of a piece influence the problems of floorcraft? It seems quite plausible. What the log-jam video shows is that small errors accumulate over time. It seems reasonable to suppose that when everyone stops, they sort themselves out and start again.
It also seems quite possibly testable. DJ readers: is this something you think you already knew?
I've divided it into traditional and nuevo because the mix of lengths seems to be very different, and that difference presents a problem for testing Ghost's theory — the problem of controlling for musical style. You'd have to play short and long tracks in the same general style, and ideally in the same tanda, to make a good test. Then, of course, you would have to work out some way of measuring the results, ideally without relying on self-reporting. A video camera placed well above the floor might be one possible way.
In the traditional tracks, there isn't that big a range to work with. Now, that could be because traditional compositions have been subject to a longer period of selection by dancers and DJs, and have converged on an optimum range of lengths for dancing. Or it could be because they were written to be played live, and musicians prefer short ones, whereas CD players don't care. Or both, or something else. I don't think my classification of any track as one genre or the other would be controversial; my collection's not that interesting.
It's also small, and contains a lot of Di Sarli in proportion to the total, so that may be distorting the results. Here are the numbers:
Traditional NuevoI think that traditional music also includes more milongas and valses, and maybe these are characteristically short; I have not looked at that. It might be interesting to do so. If you were going to test the effect of length on the number of bumps, it might be very good to do so in a tanda of milonga or vals, because the relatively fixed rhythmic patterns would somewhat smooth out the differences between individual pieces of music. But you'd need a big music collection, I think.
1:30-2:00 1 1
2:00-2:29 27 1
2:30-2:59 101 8
3:00-3:29 46 4
3:30-3:59 13 7
4:00-4:29 2 4
4:30-4:59 1 2
5:00-5:29 0 1
5:30-5:59 0 1
6:00-6:29 0 2
6:30-6:59 0 0
7:00-7:30 0 1
In the comments (or by email) I invite you to suggest a possible three or four-track tanda that could be used to measure the effect of track length, if any, on bumps.
Or, of course, you can say whatever you want in the usual way.