Building The Worlds Heaviest Airplane

When Microsoft and IBM were working on OS/2 together (this was some time ago now), MicrosoftCorporation sent a bunch of programmers to work with the IBM team, who had already done some development. The two cultures clashed in a big way, however, and IBM eventually complained that the Microsoft programmers were having a negative effect on productivity.

How was that conclusion reached? IBM measured productivity in terms of number of lines of code produced. Microsoft programmers were coming in and taking the bloated code produced by IBM programmers and simplifying it to fewer lines of code. The metric showed a net loss of productivity since the total number of lines of code was going down. NegativeLinesOfCode.

Bill Gates said it was like IBM was racing to build the world's heaviest airplane.

Ah, but Microsoft is often accused of building lighter airplanes that crash often....

-- ToddCoram

It's worth noting that, although I have heard this story many times, I have never seen an authoritative attribution. In many ways, it's like those claims, occasionally made, that Bill Gates was an incredible programmer and that his code was the leanest, meanest, and tightest code that people had ever seen.

There are at least three major implausibilities: (1)That Microsoft programmers were, to the extent implied, simply rewriting IBM programmers's code, (2) That the people who went on to produce Windows NT were producing significantly leaner code than the people who, after the split, produced OS/2, and (3) The implicit claim that "more lines" is "bloated" and that "fewer lines' corresponds to "simplified."

What's more, even if the story is true, the behavior attributed to the M'Soft programmers is a bona-fide example of bad practice. Not only did they not add functionality (instead focusing on trimming other people's code), they also removed expertise (the original programmers were no longer experts in the code they had written), they stepped on people's toes (would you like it if someone else, who was supposed to be doing something different, instead spent their time rewriting your code) etcetera.

It's an interesting story. It's mostly put about by people claiming nice things about Microsoft and, even if we stipulate that it's 100% correct, it really says bad things about Microsoft's behavior.

I agree that the story may or may not be true, but I also have an observation. The ethics of what the MS programmers did is really culturally relative. If they do not practice code ownership, and every anecdote that I've heard supports this, doing rewrites of other people's code is not too bad from their point of view. Heck, they even like to rewrite standards.

Could it be that ego-less programming can become superego-less programming? This is not the typical migration, but it can be a side effect of GroupThink. -- MichaelFeathers
The story may be overstated but it the overall message is true. Lines of code are not a good measure of productivity. It is like paying a salesman according to how many miles he's driven in his car rather than how many widgets he's sold. I've certainly had days when my "productivity" was negative by this measure; when the only way to add a feature or fix a bug was to tear out several pages of verbose, repetitive, inefficient and difficult to read code and replace it with some short, clean, efficient and maintainable. -- DaveHarris

Lines of code as a measure of productivity is horrible. No problem there. And yes, egoless programming is often a good thing. But what we have in the anecdote is, in the course of a single project, IBM people writing code and Microsoft people(who almost certainly have their own set of tasks) rewriting it.

Which, I suspect, is horrible project management.

Not only that, but the claimed superiority of the newer code is attributed to superior skill, rather than the "rewrite effect" (we all do better on a second pass, even if the first pass was by somebody else). Which means that the conclusion of the anecdote is also pretty implausible.

Ah well, I'm being hypercritical.


I don't think that the claim that the code is better translates into a claim of superior skill. Quite the opposite. It seems to me that the point of the story (which may be apocryphal, I admit) is that because the _culture_ of IBM required that productivity be measured according to lines of code produced, even the best of programmers are going to produce bloatware. It is a cultural norm. If you can't adapt to such a system, you are better off finding a job elsewhere because you are going to be mighty unhappy.

I'd also wish the product was something other than OS/2. Many people have a religious zeal toward this product. All I can offer is the suggestion that you keep in mind we are talking about OS/2 1.0, which by all accounts was a grotesque piece of code. IBM hated it so much that it threw it out completely and started from scratch, I understand. And perhaps IBMs processes were more sensible by then.

As to the question of whether other people should work on code, this gets to the heart of TheCathedralAndTheBazaar argument. Linux has shown that many eyes make for shallow bugs, and you can have many people making changes to code without losing control. Is it better or worse? That depends on which side you come down on in the argument.

-- BruceAtherton

The story I heard had MS programmers irritating IBM by dressing like slobs, showing up late for work, cooking coffee in their cubes, maliciously reducing the line count, and holding impromptu Frisbee games on the lawn, so I have no reason to doubt any of it.

Similarly, I heard that BillGates, in MS's Albuquerque days, had a habit of noticing some engineer's code unattended, then with a spasm of inspiration just f---ing it up horribly trying to improve it. Authority vs Responsibility, folks! --PhlIp

I have also heard most of these stories about Apple and IBM (Taligent era), so best taken with a grain of salt.

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