Well, I assume discretion is a huge part of this type of work. Otherwise who'd hire them right? But it really is reckless, but that's probably the point. Walts getting out of control. Before they had Mike vetting their contacts before he worked with them, so he was somewhat protected. But Mike put them in contact with Todd's boss, not Todd. Now Todd is putting them in contact with his nazi uncle, and we have no idea how trustworthy Todd is as a lone operator.
I can see the logic behind killing everyone in a 2 minute window. The second the first couple are killed they're putting the rest on lockdown. But I'm guessing there's a huge chunk of ego involved in orchestrating the whole thing within such tight restraints. Sort of like the ego involved in getting his meth to the highest % possible. I doubt Walt had any idea of the market value of his meth when he was originally making it. He was just doing it that way because of his own personal standards. He feels like a kingpin now so if he wants everyone dead in a 2 minute window, then he's going to get it.