Allah's apostle condones lying?

Volume 3, Book 49, Number 857:
Narrated Um Kulthum bint Uqba:
That she heard Allah's Apostle saying, "He who makes peace between the people by inventing good information or saying good things, is not a liar."

What is a lie:

I) a lie = false information
II) inventing information (whether goood or bad) = false information
III) therefore: a lie = false information = inventing information (whether goood or bad)

What is a liar:

I) Person telling lies

Therefore; a person inventing good information to make peace between people is a liar.

Although Mohammad's intentions in this situation seem good, there are many problems with this warped sense of morality:
1) Wouldnt peace not last, and actually aggravate the conflict once the parties knew they were lied to?
2) Does Mohammad's example apply to any situation in order to ensure peace?
a) i.e. If you cheat on your wife, and know she will be upset, would it be better to lie to her that you did not cheat on her so she will not be upset?
b) Would it be ok for Egyptian Muslims to lie to Palestinian Muslims that Egyptians will provide the Palestinians with food aid so Palestinians would not riot? (And then exile the Palestinians back to where they came from once the situation has been resolved)?
c) Is it ok for Persian Muslims to lie to Bahrain and Qatar that they have no desire on expanding their country when they send hundreds of thousands of Persian migrants to those countries to effectively make the population of Persian Gulf countries Persians?
3) Does Mohammad believe that two sides of a conflict will easily be swayed by lies of individuals?
4) Does Bukhari include this verse to show how short-sighted Mohammad was regarding conflict resolution?