The only thing that matters is that one sends a message that is understood by the recipient. The rules of grammar are only necessary when you need to modify the deviations you used in the msg if the recipient doesn't understand them. Likely, the person will learn the deviations and the rules of grammar will not be needed again for those particular deviations with that particular recipient.
The more recipients you have, the more rules --and less deviations-- you may need to apply to your msg so that all the recipients understand it.
Edited by EnderWiggin, 27 January 2013 - 02:09 PM.