The term "jitter" usually refers to variations in the sample clock driving the ADC/DAC, and the audible effects of this are increased distortion rather than any lack of "grooviness". Thats what I was talking about in my post above.
I think the RME article is refering to midi timing jitter, which is rather different. Might I suggest that if you continue to use the term jitter, qualify it as "midi jitter" or "latency jitter" as RME do to avoid confusion.