[dalke]

Not at all. The very phrasing "carry themselves properly" makes me bristle. From what I've seen of etiquette teaching services, the rules taught have about as much relevance good behavior as as "Elements of Style" has to how English is actually used. Modifying from Pullum's criticism of the latter, it's "uninformed bossiness ... and the result is a nation of educated people who know they feel vaguely anxious and insecure."

[debacle]

As is the case with both The Elements of Style and etiquette or any 'art,' you need to know the rules before you can break them.

[dalke]

My point is that many of them are bad rules ... easy to memorize, but bad rules. As a simple example, "However. In the meaning nevertheless, not to come first in its sentence or clause." That's not how English was used 100 years ago, nor how it's used now, so it's pointless rule to learn. And famously, three of Strunk and White's four examples of how to rewrite the passive into better form don't actually involve a passive. Only in retrospect do I understand why I was so confused about "avoiding the passive" during school - my teachers didn't know what a passive was!

Etiquette rules are often the same. Why stand for the "Hallelujah" chorus? Because that's the done thing. Why do people in the US eat with the fork inverted from the way used in the UK? Why is port always passed to the left in the UK, and how is the Bishop of Norwich involved?

The real answer is two-fold. Knowing these practices indicate the you are a member of a certain group. By not knowing them you can feel like an outsider. If there really are a set of easily-learned rules to follow, then you can make the transition to that group. (Jumping back to Element of Style; follow these rules to become a better writer.)

But only rarely is there a simple set of rules to follow - like if you were to meet the Queen of England. It takes years to learn the little rules that a given subgroup acquired over decades, not the few weeks these classes usually do. Plus, etiquette classes usually promote etiquette rules specific to a certain style of upper-class culture, and direct their marketing to people of lower social/economic class. The end result is that they encourage a feeling of vague anxiety and nervousness in their target audience, and perhaps also a sense of superiority in those in the upper-class who learned these rules growing up.

The other fold is that there are some bad things which are easily avoided with preparation. Don't wear orange at a big, rowdy St. Patrick's Day party in Boston unless you're itching for a fight. Those especially occur when mixing very different cultures; eg, in part of the world "Chopsticks should not be left standing vertically in a bowl of rice or other food" because they have a funeral connotation. Cultural awareness training for this case, especially for people moving overseas to a radically different culture, can be very fruitful.

However, as the original poster said "carry themselves properly", I presume the courses are of the first fold - promotion of certain economically upper-class practices - and not the second - avoiding culture clashes.

In any case, it isn't a matter of learning rules before you can break them. It's a matter of learning specific rules in order to appeal to those who believe that those rules are meaningful, whether it be an editor who rejects ".. or less" as valid English, or a person who thinks only buffoons wear white after Labor Day. With that in mind, "carry themselves properly" is not longer absolute but only meaningful if you want to get something from that subgroup of people.