# Discussion: Preliminary Course Notes

in: Sprint San Diego (May 25–27 - San Diego, CA, US)

May 15, 2024 5:27 AM
After vetting is completed, there will be updates.

Here's the Intro page to the Preliminary Course Notes,
and there are links to the 5 different stages.

Not too late to register, as of this posting, there are 29 open slots.
Main event page.
May 17, 2024 6:27 PM
Hi Rex, what is butterfly loop?
May 17, 2024 6:37 PM
A set of butterfly loops (minimum of two, but could be more) is a way to split apart packs of runners as they arrive together.

Examples of control sequences with two butterfly loops:
Runner A: 1-2-3*- (4-5-6) - 7*- (8-9-10) - 11*
Runner B: 1-2-3*- (8-9-10) - 7* - (4-5-6) - 11*

Runner A does the 4-5-6 loop first, followed by the 8-9-10 loop. Runner B has the opposite permutation.

The * control is the same exact control, visited 3 times (in this case, #3 to start the first loop, #7 to finish the first loop and start the second, and #11 to finish the second loop.

When both Runner A and Runner B reach #11, they have run the same set of legs, but in different orders.

If you have more loops, then you'd have to keep coming back to the common control more times. With more loops comes more possible permutations to split runners up.

They are called butterfly loops because on a map, the central control is the body of the butterfly, and the loops are the wings.
May 17, 2024 10:08 PM
May 17, 2024 10:40 PM
J-J thatâ€™s clearly an 8 not a butterfly stop confusing people.
May 18, 2024 12:58 AM
May 18, 2024 1:22 AM
I love that you found (made?) a new example instead of just rotating the original and having the numbers be sideways.
May 18, 2024 1:39 AM
It was easier than doing "all that work". The second one is from the OUSA Team blog. (But I love all the depressions in the first one.)
May 18, 2024 4:24 AM
They all beat me to the punch! Good visuals.