Great question — answering as the UphillTech team:
Yes it is was. But since Ubuntu 12.10 linux-generic depends both on image and headers metapackages: linux-generic ─┐ ├─ linux-image-generic ─ linux-image-VERSION-generic │ ┄ linux-image-OLD_VERSION-generic │ ┄ linux-image-ANCIENT_VERSION-generic │ └─ linux-headers-generic ─ linux-headers-VERSION-generic ┄ linux-headers-OLD_VERSION-generic ┄ linux-headers-ANCIENT_VERSION-generic But I cannot explain why it was that way over mutiple release cycles. If you look at Ubuntu package search and look at all versions you will see at least the Hardy linux-generic package depends on two meta-packages (-image-generic and -restricted-modules-generic).
Full answer by Lasall: https://askubuntu.stackexchange.com/a/197615 (CC BY-SA 3.0).
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