Precision... we can and must achieve it

Just because everyone does it, that doesn't make it correct. I'm referring to the sloppy use of "can".

A senior writer in our care presented the magazine's comment piece this morning, including the exhortation: "We cannot let this affect our decision". This was changed to "We must not...". Why? Because the OED defines "can" as "be able to". The writer did not mean "We are unable to let this affect our decision" so she shouldn't have written it.

And yes, I do know that recent editions of the OED give credence to sloppy usage by admitting "be permitted to" as an alternative meaning of "can". Even Fowler's Modern English Usage (3rd edition) accepts this usage "in informal circumstances". But the 2nd edition on JD's desk doesn't, and neither do I.

English abounds in such subtleties as the difference between "may" and "can". We should not sacrifice precision simply because a generation of schoolkids (and graduates) have not been taught to pick their words carefully.