Note the shortcomings, though:

- if you want layout modifiers, they must be included here; there is no way to apply the layoutHook's layout modifiers to something not in the layoutHook.

- layouts store state in their constructors in the layoutHook. This state will probably be inaccessible.

- the layout and its state will be lost across mod-q because only the layoutHook is saved across invocations. No, it is not possible to save the keybindings on the off chance that someone hid a layout inside them.

- layout modifiers with runtime behavior, as a result of the above, will either not have that behavior or will malfunction in various ways. (Example: mod-b to toggle struts would only toggle them in the layoutHook.

- some runtime behavior is accomplished via sending messages to layouts. This, again, expects those layouts to be reachable via the manageHook, and often requires some state. At the very least, I expect broadcast messages will not reach your layout.

- other things that know that the layout is reachable from layoutHook will break. I'm not thinking of any off the top of my head, but it's not unlikely that something in the xmonad core cares.