Anki (both 2.1.40 for Windows and AnkiDroid 2.14.3, both with 2.1 scheduler enabled) has an issue of showing siblings one after another without putting other cards between them.
Details:
I created a filtered deck. I have only learning and review cards in it, no new cards. Each note has 2 cards. Anki shows me the front card and then immediately the back card of the same note. After answering front card I can immediately easily answer the back card, but this “Easy” grade is fake. My memory does not work if I’m asked a card immediately after answering another card of the same note. The filtered deck has about 200 cards, so it should be feasible for Anki to delay reverse sibling card and show it after some other cards, but it keeps showing siblings one after another. In the home deck I have “Bury related new cards until the next day” unchecked (should not be an issue as the filtered deck does not have new cards). “Bury related reviews until the next day” is checked. I know that burying does not apply to learning cards, but Anki could space siblings of cards by a number of minutes. For instance, Anki could space due siblings (new/learning/review) in the same deck (usual or filtered) by 10 min. So, after I answer sibling 1, I will answer other cards before I see sibling 2 in 10 min., then I will answer other cards before I see sibling 3 in 10 more min., etc. Or maybe Anki could space siblings based on a number of cards of other notes between them, instead of a number of minutes.
I thought that maybe Delay Siblings addon could help. But it does not work for this. It seems that it works only for review cards with longer intervals.