Ok, I've identified the root of my confusion here. Mochi has two FAQs:
https://mochi.cards/faq.html Mochi uses SM-2 without EF adjustment and without resetting intervals. This is outdated.
https://mochi.cards/docs/faq/ says Mochi multiplies by a number >1 on recall and by a number in [0,1] on forgetting. This FAQ is linked from the front page and seems to be the correct one.
And, indeed, checking the review settings for my deck shows the multiplier settings.
Hey sorry about that. I will take down the old FAQ, or at least redirect it to the new one. The other thing not mentioned in that section of the FAQ (that I will add now) is the re-review phase. When you miss a card during review it will go to the re-review queue. Missing it again in that phase will reset its interval to 1.
Since I created Mochi there have been some new algorithis developed. Most notably FSRS [0] looks promising.
https://mochi.cards/faq.html Mochi uses SM-2 without EF adjustment and without resetting intervals. This is outdated.
https://mochi.cards/docs/faq/ says Mochi multiplies by a number >1 on recall and by a number in [0,1] on forgetting. This FAQ is linked from the front page and seems to be the correct one.
And, indeed, checking the review settings for my deck shows the multiplier settings.