English majors, is there a word for this?

[Flickerdart]

We all know how English likes naming rhetorical devices. Exaggeration for comedic effect? Name for it. Understatement for comedic effect? Yep. But is there a name for intentionally poor spelling/grammar for comedic effect (such as the last two panels of this comic (http://www.vgcats.com/comics/?strip_id=155))?

[SaintRidley]

We actually cribbed most of the names for rhetorical devices from classical rhetoric (go figure), which is why most if not all of them work both in speech and writing. The phenomenon you're asking about is purely written, but it does have a term: cacography (http://en.wikipedia.org/wiki/Cacography).

In the context of discussing rhetorical devices, cacography should serve. Should you need to explicitly note that it is intentional, just say intentional cacography.

[BWR]

"Hyperbole" is intentional exaggeration for effect, but not necessarily for comic effect.
Likewise, "Meiosis" is an intentional understatement, but not necessarily comedic.

[Ebon_Drake]

It possibly qualifies as Pronunciation Respelling, where words are written as they would be said. However, that's more used to reflect a character's accent in writing (such as with Durkon) rather than specifically for comedy.