I would think it has to do w/ ecomonics. Cakewalk started out as a midi squencer, then added audio, then other means of "inputting" sound.
I doubt if 10% of SONAR users extensively use notation, who have stuck w/ SONAR up to now. I imagine if someone really needs notation they have a notation program (that costs as much as SONAR itself). Cake did make XML (is that right?) exportable in X1. With such a small base, it hardly warrents spending money to expand notation that most likely won't lead to further sales.
Sorry, that is the way it is. If Cake thought they could make money expanding notation, they would do it. They haven't, ergo.
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