Considering Hand vs Machine must not be judged based on the fact that perhaps MOST of the hand counters, even in King County, are honest Americans - both Dem and Pub. The issue as I see it is that in a hand count, the counters that are working against the system can do ALOT more damage to the process than a machine. The [rotton] human can read the news, use the phone, call the hacks, etc... and know the quantity of votes required and then, based on that persons job, do all he or she can to cheat.
I was an election official in a union election back in the 70's. It was the first total mail-in election in our local.
To avoid controversy, we requested the US Dept. of Labor to oversee the entire election.
As both sides trusted me, I was the "official" ballot reader. As the vote was very one-sided, I made a few mistakes.(It's hard to say "Jones" ten times in a row, then switch to "Smith") They were immediately caught and corrected. Those poll watchers looking over my shoulder were not going to let anything get by. I welcomed their presence as this assured that no one could accuse me of anything.
The point is, with all the legal controls in place, a hand count is as accurate as any machine, and it is out in the open where everyone can see it. Also, done at the precinct level, it would not take an inordinate amount of time.
A machine (computer) is only as honest as the person who programmed it. I'm no expert, but I bet it could be programmed to add (or subtract) a vote or two at some specific interval.