Comment by layer8

I guess your conception is that one could then define

    <dead_acute> : <combining_acute_accent>

instead and use it for arbitrary letters. However, that would fail in locales using a non-Unicode encoding such as iso-8859-1 that only contain the combined character. Unless you have the input system post-process the mapped input again to normalize it to e.g. NFC before passing it on to the application, in which case the combination has to be reparsed anyway. So I don’t see what would be gained with regard to ease of parsing.

If you want to define such a key, you can probably still do it, you’ll just have to press it in the opposite order and use backspace if you want to cancel it.

The fact that dead keys happen to be prefix is in principle arbitrary, they could as well be suffix. On physical typewriters, suffix was more customary I think, i.e. you’d backspace over the character you want to accent and type the accent on top of it. To obtain just the accent, you combine it with Space either way.