If you were asked to do a training/set of trainings for support staff in a large firm (PAs and DAs to Archivists) on Business wrtiting and Business English, what topics would you choose?

Basically, I have been told to design something which will improve their skills, but is not a language lesson.

Any ideas on topics which wont make them groan?

Would you leave anything out or add anything?

formal and "business casual" vs. informal
word choice and it’s importance in terms of image and tone
tone and remaining polite even when you want to explode
sounding more English (avoiding russisms)
tips for writing in English
grammar and punctuation and their importance
style of solid business communication
keys to solid writing: clarity, brevity, consistency, relevancy
punctuation
business terms specific to certain groups/fields
email etiquette
phone etiquette
sounding smart but not aloof

And some of these (punctuation) were requested by those who will participate.

Be Concise, Specific, Coherent, and Complete in Business Letters
Additional guidelines that business-letter writers should keep in mind include the following:

Avoid verbosity: Time is a valuable commodity, and most people have no desire to wade through an entire paragraph in search of the writer’s meaning. Then again, people should never be so abrupt as to appear rude or curt. They should, however, omit irrelevant, excess verbiage and strive for conciseness.
Avoid non-specific writing: People should think through what they intend to say before they put their ideas on paper by asking themselves, “Will the recipient know what I mean? Will he know to whom I am referring?” If the answer is “no,” then they should make those points clear.
Avoid incoherence: A reader should not have to guess how a writer’s thoughts are related, which is why knowledgeable writers use transitions or “connecting words” to relate ideas. For example, they use such words and phrases as “for example, however, moreover, as a result, since, on the other hand,” etc.
Avoid incompleteness: Perhaps because they fear being verbose, some people make the mistake of being overly concise and, as a result, often omit essential information. For example, as Zimmer points out, a writer may know all of the specifics about a purchase order, but since the reader may not have this information at hand, then he or she will have to devote valuable time to locating the information.
http://factory-facilities-operations.suite101.com/article.cfm/effective_business_communications_and_writing

delta
yeah false friends will be there
AE vs. BE need to add. Thanks!

that's great!

I agree with some of what's already been said (SirReal, Supa Translata). Susan, as I understand, your target audience is somewhat of a hodgepodge, so it would make exceedingly hard to cover all of the topics you outlined and make your training useful for everybody. I would stick to the basics (bare bones, really) of English composition, especially when it's applied to writing business letters. I would do a lot of "good example" - "bad example" sort of thing, and I would give them a lot of ready-made sentences, with their Russian translations.

And yes, I am an ACTUAL LIVING BREATHING (ИНОГДА ОЩИБАЮЩИЙ) NATIVE.

"Swoosh is the PERFECT candidate for the "how not to come across as a complete asshole" portion of the training... )))" hahahah! No offence meant.

OTHERS: As this monster really is a hodgepodge kind of group, thanks for the advice!

And yes, I am an ACTUAL LIVING BREATHING (ИНОГДА ОЩИБАЮЩИЙ) NATIVE.

"Swoosh is the PERFECT candidate for the "how not to come across as a complete asshole" portion of the training... )))" hahahah! No offence meant.

OTHERS: As this monster really is a hodgepodge kind of group, thanks for the advice!