I disagree with point 2. You only alienate the talent if you don't have a culture of exploration. On several occassions I've hired exceptionally bright people, with no clear idea what they might do. In every case they figure out what to do, usually by finding a gap that we didn't even know we had.
Some very smart people are just looking for a place where they can experiment and grow technically and do the basic things they love. If you can utilize these people without having them end up building and testing CRUD apps to justify the headcount, that's fine.
But other very smart people want not only to be doing interesting things, but also to be as close to the money as possible. What they work on needs to have an impact, and have some chance of setting the direction of the company.
If you accidentally hire that latter person into a role designed for the former person, they'll get bored, or, worse, irritated when they try to get close to the money and then rebuffed (or, worse, pigeonholed into something boring).
What I'm saying is, be careful with the notion that you can always find something for an A-player to do. Often, no.
There is a degree of truth in this point. I will also add, though, that some of our best hires aren't doing anything remotely like what we hired them to do...
Definitely a principle of the lean startup, which leaves out the possibility of what potential bright minds can do to expand a company's horizon. This point mainly points out on core competency: do what you do best and let the others do what they're really good at.
But it doesn't leave room for opening to other perspectives and untapped creative ideas from different sources.
