More Useful Table confusion

Can someone help me understand why my goal https://www.beeminder.com/drtall/goals/drinks_triangle is showing the values it is for the Hard Caps By Day table?

For posterity I am looking at https://www.dropbox.com/s/xsskbz64792j10h/Screenshot%202015-09-02%2011.08.20.png?dl=0 .

Tomorrow (Sep 3) the road is going to flatten so I’d expect a delta of +5 (since it’s always measuring from today). But I know there’s some funny business about the road width changing when the slope changes, but surely I’m not going to actually get +36 (+41 - +5) tomorrow?? That would be a bonus of more than an entire week’s worth of points for this Do Less goal.

Any ideas?

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That’s so confusing and it’s not exactly a bug but it’s Beeminder being way too clever for its own good. Pull up a chair and kick off your shoes while I explain…

For some reason (I’ll be interested to hear if this was intentional on your part) after that upcoming flat spot you’re allowing 252 units per week (36 per day). Flat spots, according to the raw algorithm for road width should have zero width but that catches people by surprise when they thought they made it to the flat spot and, oops, the road shrinks out from under them and they have one more eep day [1]. So we special-cased it so that the road width of a flat spot is the max of the width of the road on either end of it. Maximally conservative and friendly, which is always a horrible idea in beeminderland, where leniency always backfires.

Anyway, but that’s what we did and that’s why you can suddenly do an extra 36 drinks/units/points/whatever on the day the flat spot starts. This will all get solved when we undertake the big refactoring proposed sagely by @insti of treating the graph as having a yellow brick halfplane instead of a road with a centerline. Namely, the critical edge should be the only thing that’s relevant. Dialing the centerline and having the critical edge follow it some varying width away leads to messes like this.

Also thank you so much for the alert that something seemed awry. It is, and it runs deep!

Oh, and workaround: change the slope after the flat spot.

[1] Sadly this very problem still happens if you just schedule a shallow spot instead of a flat spot.

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Yes, this is intentional. This is me taking ~3 weeks off drinking and then going straight to a bachelor party. I want effectively unlimited points for that weekend (after which I’m going to retroratchet) but I still want to track the data so I don’t want to archive the goal.

You may consider me 100% caught by surprise.

I tried this but it doesn’t seem to have had any effect. I scheduled a 1 day break at the old rate before the huge weekend but the road width doesn’t seem to have changed.

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Ah, lack of a proper road editor is so frustrating! (I predict that when we get that deployed, despite reservations about it being more of a power user thing that shouldn’t be top priority, we’re going to shake our heads in disbelief that we ever considered Beeminder usable without it.)

Anyway, I fixed it for you with the admin-only road editor in the meantime! Sorry for the hassle here and thanks again for reporting the ridiculousness!

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This!

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Thanks!