Okay, having done some more reading, it seems that JSF takes it upon itself to generate id values (and name values) for components in a composite, which is why I can't set the id on the inputText without it being modified.
But does that mean it's impossible to match a "for" attribute in a label or a message with an "id" attribute of an input field? (without some ugly hack like doubling up the supplied id in the "for" fields to make them match the value generated in the "id" field. I am sure something like that cannot be relied upon in future releases)
It would seem that if I am supplying the id value myself, I should at least have the option of telling JSF not to fiddle with it.
(Or am I still missing something... which is quite likely!)
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