A general rule of thumb is that the more flexible person adapt socially to the person with the more rigid customs. "When in Rome," and all that. Paul, in the New Testament, has a number of instructions to his disciples along the lines of adapting to the customs, diet, and other trivial characteristics of the people they are preaching to. This allows one to deal with the more important aspects of things.

This flexibity, of course, applies to social customs and other such niceties, and not to moral principles and such.

So, if you are dealing with a person from a culture that does not like bluntness, ideally one would try to ease back. Think Japan. Admittedly, I am not that good at doing this.