Sorry, I assumed that 80% and 86% were close enough that a reasonable reader would be able to see that I had mis-remembered the second significant figure for statistics I heard a while ago.
My apologies.
> easy test: would you continue to work on linux with the same pace/effort if your company stopped paying you for it? yes/no?
Yes (though my work is not generally kernel work, I would still continue to contribute to the free software projects I currently work on at the same pace).
> if you answer yes then i also expect you to pay them back any past salaries you cheated out of them ;).
... why? An employer pays you to solve technical problems that rise from their business. That doesn't mean that as an individual I wouldn't work on similar problems anyway, it just means that I get paid to work on specific problems rather than whatever I find important.
Effectively an employer pays you to change your priorities to match your employer's priorities. How much your priorities actually changed is not relevant.
Let me ask you a question. If one of your customers found a security issue in grsecurity or found that one of the features of grsecurity was broken, would you prioritise fixing it over whatever interesting feature you were working on "in your spare time"? If yes, then congratulations you're paid to develop grsecurity. If no, then I wouldn't pay you for support because I would have gained very little for my support contract.
> in our case, it's not 'some time' but 'all the time'.
You can continue to claim that, and I will continue to call bullshit. While you might be able to argue semantics and say "technically we never were paid for any particular features" I find such discussion disingenuous.
> puts the original statement into a very different light:
That statement doesn't say "developed for free" it says "provided for free". If it said "developed for free" I wouldn't agree with it. But by the same token I don't agree that there isn't a significant proportion of development that is not paid, and I don't lend credence to hypothetical predictions about how Linux would be developed without anyone being paid.
Despite what you say, Linux was developed for free for the first year or so and was mostly developed for free for several more years.