I think what offends examiners and employers when confronted with extremely informal, unpunctuated and haywire language is the implication of not caring that underlies it. You slip into a suit for an interview and you dress your language up too. You can wear what you like linguistically or sartorially when you’re at home or with friends, but most people accept the need to smarten up under some circumstances – it’s only considerate. But that is an issue of fitness, of suitability, it has nothing to do with correctness. There no right language or wrong language any more than are right or wrong clothes. Context, convention and circumstance are all.