nant_0.91~alpha2+dfsg-3_all.deb in Ubuntu 12.04 and earlier actually ignored these due to a bug
However, nant 0.92~rc1+dfsg-2 in Ubuntu 12.10 fixes this bug (possibly https://github.com/nant/nant/pull/39).
Which makes nant time-consumingly copy these files when the aren't actually used.
Tested removal of <copy> on both nant 0.91 and nant 0.92
Will be submitting this patch to prebuild project for comment though I suspect there's nobody there to pay attention.
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