A nice article! It really does a great job of describing the hostage nature of keeping the various daimyo in check.

One thing that I think is commonly misstated though, is that this period was one of "peace".

When viewed from the elite perspective, the power struggles between daimyo in the Warring States Era had subsided, but for the common people, the Edo Period was anything but peaceful.

The samurai class could chop up any commoner at any time, for any reason, or no reason. Sometimes just to "test" a new sword, or because their "honor" had been challenged (maybe the person didn't get out of the way and bow fast enough).