What it sounds to me it's saying is that 0xF8 can come along at any time, so one should explicitly check for it at every Serial.read(), lest it come after a status byte and before a data byte, no? And at that Serial.read(), one should not update the "current status" if it receives a status byte of 0xF8 or higher.
In other words, let's take my initial example:
144, 60, 80
60, 0
The way I have it implemented now is that when a status byte is received, it gets put in the status buffer. So upon reading 144, 60, 80, 144 goes into the status byte buffer. When 60 and 0 is received, since status hasn't changed, it assumes 144, 60, 0 as the MIDI command. If an 0xF8 (248) timing byte ends up in the middle there (let us suppose a stream of 144, 60, 80, 248/0xF8, 60, 0), the status byte gets updated to 248 (with the way the code is currently written) and everything gets screwed up. The 0xF8 should be processed on its own, and then the next two bytes that are data bytes should be read and processed as note and velocity bytes for the status of 144 (noteOn/channel 1).
I have no reason to plan for this contingency, as I'm not going to be using the device in such a manner, but is my understanding incorrect?