BCHR is yet another in a long line of metrics that *can* tell you when your databases are performing well, but don't tell the entire story themselves. It is always important to monitor performance at the application layer as well, rather than relying fully on server metrics.
Eh, I am biased as an app developer, more often then not I find network and database issues to be more pertinant then any type of application errors/performance issues. I find this to be more of an issue if the application was archtected improperly from the very beginning.
Well, I didn't mean to blame the application. I just meant that rather than watching only performance counters to monitor application health/performance, we should be watching the application and using the counters to help diagnose issues when they arise, instead of treating them as indicators of performance issues.