Ok, lets look at that for a moment.

This comment: "I don't think that anyone actually adopts this position. You would probably not become a kidney donor for your customer, or pay them $10,000 because they confess to you in a support call that they recently became unemployed. You would not build a new software application just for them. You would not even add a feature to the product just for one customer! (At least at the consumer software level.)" seems a bit like reductio ad asurdum right? Of course you wouldn't donate a kidney. The argument goes you solve their problems that are blocking their use of your product. In the anecdote the customer Bob didn't have quite the computer skills they needed, but those skills were essential to being able to run the product platform. So our author helped them develop those skills. Note that this person has already paid for and bought the product so they are already a customer.

"I guess the fundamental problem I have with your position is that you are preaching a message that lots of people in Fortune 500s should hear (and won't), to a group of people that are probably treating their customers too well already, and are perhaps feeling guilty that they do not do even more for them, and are thus primed to further the error. So in that specific sense, I think this advice is dangerous."

I disagree with that too, consider the AirBnB case of the customer who had her apartment trashed. That was a case where a non-fortune 500 company initially took the position of 'do what is best to protect the company', got a ton of criticism for it, and then turned around and focused more on making the customer whole before counting costs on the company. The latter was much more successful, and AirBnB has remained a steadily growing company. And they learned from that experience both how to be more customer focused and how to protect themselves in the future. If you have one customer, or ten, or ten thousand, every time you help one of them through a problem of using your product your company and your product gets better.

There are some great examples of great customer service in many YC companies and amongst folks here. There are also some less than great examples.

Then you finish with this, "... to a group of people that are probably treating their customers too well already, and are perhaps feeling guilty that they do not do even more for them, and are thus primed to further the error." which completely jumps off the rails. Small companies are busy places, and if the customers aren't having problems then generally they aren't taking any resources away. Its good to periodically poll them and ask how they are doing but there is never a risk of deciding to go just go out looking for customer problems to solve, if the company is focused on getting the product out the door.

So I started at Sun on the Monday after they went public. They were still a pretty small company < 2000 employees they were not a fortune 500 company yet, but they were very customer focused. I joined Network Appliance the Monday after their first layoff in their history, they weren't a fortune 500 company yet, but they were customer focused. My point is that being customer focused isn't something you 'add on' when you get big, it is something you 'build in' when you are small and you nurture. I strongly believe it contributes to the success probability.