There have been about 30,000 days since he started working in 1930. If the 300,000 number is accurate, he would have had to fix an average of 10 typewriters, every day, for the past 80 years. That's without any weekends or holidays.

I guess I have no direct experience repairing typewriters. However, I would have certainly guessed that it takes longer than ~1 hour to "fix" a typewriter. In addition to that, I would think it's hard to find a stream of that many typewriters to repair. (I.e., a rather successful business.) If these numbers are true, the guy was pretty impressive.

Actually, mains power should normally be a very good frequency source for a clock. Utilities periodically adjust the frequency such that the long term clock drift is near zero. From wikipedia:

So yes, 1w is a lot of power.

The parent's point was not to say that 1W is useless. (Indeed, as you point out, 1W can be put to great use.)

Instead, he made a very logical argument that if society's goal is to reduce wasted energy (a noble goal), then it is misguided to try to expend tremendous engineering effort trying to reduce a device from 1W down to 0W. If, instead, we improved the efficiency of a 75,000W SUV by a mere 0.1%, we will have saved two orders of magnitude more energy.

Attack the biggest problems first, not the smallest ones.

I believe that TFS means 'the only known recording of a particular live Woody Guthrie performance'.