The Alan Kay quote does not say you should waste 90% of your time, Kay says you should fail 90% of the time. It is only wasted time if you don't learn from your failures.

Further, the quote in the original post from Hamming is that "at least 50% of the time must go for the presentation." Hamming does not call preparation and presentation "waste". Reading the Hamming quotes, I find nothing that indicates he thought being friendly, conforming, making, or giving presentations was wasted time.

On the contrary, Hamming spent quite a bit of time criticizing his contemporaries for wasted effort (his words) by ineffectively swinging their egos rather than working within the system (or judiciously bypassing the system).

@gvb the use of the word waste stems from the fact that many technical people (previously including myself) make the mistake of thinking that the time Hamming is talking about spending on presenting your ideas is waste.

Clearly, I am arguing against that in this piece.

So, instead of

.5 * 1

does that mean we should waste

.9 + .5 * .1 (90% plus 50% of the remaining 10%)

or

.5 * 1 + .5 * .9 (50% of everything plus 90% of the remaining 50%)

?

For those who don't want to run the numbers:

.9 + .5 * .1 == 95%

.5 * 1 + .5 * .9 == 95%