Originally Posted by
corporate-wage-slave
The pen signature can of course be compared to the signature sent in on the passport application form.....
But the ABTA link posted by UKtravelbear says:
The move to a handwritten signature is an essential development for improving HM Passport Office’s online application service, by removing the need for customers to send signed paper forms
which suggest that at some point there'll be no signed paper form to compare against. (I suppose a digitally capture signature could be used on an electronically submitted form, but then that would invalidate the reason for needing a manual signature on the new passport.)