Honestly, I don't really care that his calculation was based on an incorrect premise, but I do care when someone calls me a horrible failure that needs to go back to remedial arithmetic.
Because you are. Deal with it. You claimed it would be unreasonable to test and cited a hundred years of typing.
First of all, a mechanical actuator can run 24x7x365 and hey there's 31.5 million seconds in a year. Which means performing 50 million actuations at an entirely reasonable rate of 3 per second gives you 94,672,800 actuations performed per year per actuator. Or nearly two full destructive tests per year. And that's the low side - they likely do a 250ms cycle (or lower) meaning 4 actuations per second giving you 12,500,000 seconds or just 144 days for full destructive cycle.
Secondly, you seem unable to differentiate MTBF and MTTF, or use the search function properly. Which is filed under "not my problem." I'm using complex models that take a variety of factors into account including
exactly how much I type using over a decade of empirical data. You have yet to provide any equations whatsoever to back up your "100 years" claim, much less any explanation of where you got that number other than pulling it out of your ass.
But since you appear bad at math
and reading, here, I'll help you out with the basic arithmetic that proves you're full of it.
The world's fastest is 956 CPM.
There are roughly 124,800 minutes of work in a year (52 * 40).
That's 119,308,800 keystrokes in a year.
Of these 119,308,800 keystrokes, they are unevenly distributed with anywhere from 60-95% of them on just 37 keys.
That gives an average of 3,224,562 actuations per individual key presuming use of 37 keys and evenly distributed.
These 37 keys are not evenly distributed. Count the number of E's in the previous sentence as example.
Even if we falsely presume that all 37 keys are evenly distributed that gives a MTBF of 15.5 years and a realistic MTTF of <9 years.
And this is all predicated on no more than 40 hours per week of usage ever, with not more than a total of 2,080 hours of usage in a single year.
