I know it seems daft - but I have just been on a writing course , and the focus of this course was to ensure that the message you were trying to get accrss, comes accross as to puntuation, the course lead to say that comma's and fullstops are slowing merging and the use of semi-colons and commons again are merging, - they discussed this and said that grammer is a moving enity and old school grammer rules are being changes (old school being the "correct" style of grammer which we are discussiong/arguing about here), Modern grammer (or grammer full stop) was going down to a base level .
however the course did point out that any communication between two parties should be on a common level - ir if a customer complains to you and there grammer is shot to pieces then you should address your letter to this level (no fancy wording, plain english..etc.) clear and concise
where as if you had a letter from say someone of a higher educated level and they have got technical or fancy english , then you could address your letter and style to this level should you wish to, as long as your response tot he enquiry/complaint etc was clear and that the other side would understand what you were talking about.
however the course did point out that any communication between two parties should be on a common level - ir if a customer complains to you and there grammer is shot to pieces then you should address your letter to this level (no fancy wording, plain english..etc.) clear and concise
where as if you had a letter from say someone of a higher educated level and they have got technical or fancy english , then you could address your letter and style to this level should you wish to, as long as your response tot he enquiry/complaint etc was clear and that the other side would understand what you were talking about.