It depends on whether you only care about yourself, or think a little bit about others in your situation too. While the poster got himself a nicer deal, taking it only incentivizes the company to continue with this practice. After all, per one HNer who can negotiate a better arrangement, they'll have a hundred schmucks who will take the default.
Now, I understand that in real life, it's not an easy, abstract choice - you have "only human" issues playing part, like being tired and wanting to get the Internet situation sorted out ASAP. So to be clear - I'm not blaming the poster for choosing this way. But it was a suboptimal decision - and the kind of decision that lets schemes like this exist in the first place, so I wouldn't call it "beating lock-in".
I think that, for the vast majority of renters, getting a discount is about as much as you can hope for. We would all love to have the time and resources to take the telecoms to court and set a precedent, but 90% of us (probably more in SF and among Hacker News readers) don't have the luxury of doing without the Internet to make a stand.
Now, I understand that in real life, it's not an easy, abstract choice - you have "only human" issues playing part, like being tired and wanting to get the Internet situation sorted out ASAP. So to be clear - I'm not blaming the poster for choosing this way. But it was a suboptimal decision - and the kind of decision that lets schemes like this exist in the first place, so I wouldn't call it "beating lock-in".