Forum Moderators: martinibuster
No. Submit once to the best category
Follow their guidelines if you want the best chance for the site to be considered.
Ignore their guidelines if you want the best chance of it being deleted as spam.
Other directories
Read and understand their guidelines before submitting.
The principle is the same in all cases: take the time to find out what they want, and approach them with that knowledge.
Or risk (at best) being processed after they've handled the submissions that do meet their guidelines. Which, if there is a steady stream of correctly structured submissions, may be never.
There are also some exceptions made (that are not considered spam) where you can get multiple listings (i.e. DMOZ deep links) but as far as I know this is never for a commercial category.