How is a shift in communicative strategy affects the language form, duration and interaction, relationship of speaker, role and responsibilities of the speaker, and message delivery?

It affect badly in the communicative strategy.

Explanation:

The sudden shift or a sudden change in a communication badly affects the discussion or communication between the people who were in the communication. The flow of information and the interaction changes in such cases.  

When we interfere a discussion in the middle or there is a shift in the communication strategy, it affects the communication a lot in terms of information, speech context, speech style and many more. The message delivered is also stopped and some other conclusion is drawn. The responsibilities of the speaker is also hampered.

moon-letters were a method of writing invented by the dwarves. moon-letters were ordinary runes, but written in such a way that they could only be read when the light of the moon shone behind the writing. some moon-letters could be read by any moonlight, but it was possible to make the writing even more secret. more sophisticated moon-letters could only be read by the light of the same shape of moon, or at the same time of year, as when they were written. hope this !

“way of writing” should be replaced with “writing style"

“idea” should be replaced with “purpose.”

maybe   “people from a long time ago” should be replaced with “elizabethans.”