Thorsten Froehlich wrote:
> 
> In article <MPG.153d5ce5737c09fa9898b7@news.povray.org> ,
> jam### [at] ntlworldcom (Jamie Davison) wrote:
> 
> > Is this related to the saying that 'Putting twice as many programmers on
> > a project that's late makes the project twice as late'?
> 
> Wasn't that the result of a famous IBM project that turned out to be a
> perfect field study of a failing project?
> 
>       Thorsten

From http://www.tuxedo.org/~esr/jargon/html/entry/Brooks's-Law.html:

Brooks's Law prov. 

"Adding manpower to a late software project makes it later" -- a result
of the fact that the expected advantage from splitting development work
among N programmers is O(N) (that is, proportional to N), but the
complexity and communications cost associated with coordinating and then
merging their work is O(N^2) (that is, proportional to the square of N).
The quote is from Fred Brooks, a manager of IBM's OS/360 project and
author of "The Mythical Man-Month" (Addison-Wesley, 1975, ISBN
0-201-00650-2), an excellent early book on software engineering. The
myth in question has been most tersely expressed as "Programmer time is
fungible" and Brooks established conclusively that it is not. Hackers
have never forgotten his advice (though it's not the whole story; see
bazaar); too often, management still does. See also creationism,
second-system
effect, optimism."

Brooks has since migrated to graphics.  When he got the ACM Turing Award
(the closest thing CS has to a Nobel Prize), he chose to give his
acceptance speech at SIGGRAPH.

See also
http://www.tuxedo.org/~esr/jargon/html/entry/Ninety-Ninety-Rule.html:

"The first 90% of the code accounts for the first 90% of the development
time. The remaining 10% of the code accounts for the other 90% of the
development time." Attributed to Tom Cargill of Bell Labs, and
popularized by Jon Bentley's September 1985 "Bumper-Sticker Computer
Science" column in "Communications of the ACM". It was there called the
"Rule of Credibility", a name which seems not to have stuck. Other
maxims in the same vein include the law attributed to the early British
computer scientist Douglas Hartree: "The time from now until the
completion of the project tends to become constant."

-Mark Gordon

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