Your assumption that you wouldn't end up over POM at 10k and 250 is naive and inexperienced.
(a) Procedures are based on presumptions - doesn't matter whether we are talking about letdowns or how to operate a rowing boat. If the reality matches the presumption then everything runs a lot smoother ...
(b) Clearly, we don't always match the procedural presumptions for any of a host of reasons. There would be few pilots who haven't been caught out hot and high somewhere on a letdown on the odd occasion.
(i) if the pilot then perseveres in blind faith with the hope that things will work out OK - he/she ought to be in another line of business
(ii) the competent pilot simply does what he/she does routinely - recognises that the reality doesn't match the plan, figures a way to fix the problem, and then fixes it. In the case of a letdown, that might involve ATC, comms with other aircraft OCTA, whatever
... and, aterpster does have a passing knowledge of this stuff .. somewhat beyond that possessed by most of the rest of us.