The ability to consistently send out emails and other forms of media with misspellings, incorrect or missing words, incorrect or missing punctuation, and all around bad grammar. The proper way to type the word Grammahtology is in italics. One who obtains a mastery of Grammahtology is usually awarded titles signifying their prowess.
Wow, my boss really created a work of art with his latest Grammahtology email:
"This needs to be do onsite, we can scheduled this for next week. Do you have the network cabling in place?"
"Did you the cables labeled?"
Examples of titles awarded for Grammahtology mastery: TEH RIHC, The Professor, and The Butcher.