A few points that I hope you may find helpful:
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Are "My Tasks" and Google Calendar sync features broken? - #6 by Sam_Friedman1 (My answer: Yes)
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Asana has a policy of never giving a lookahead as to which features they will be addressing
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If you are reliably getting your Asana tasks to all show up in your Google calendar and update within a reasonable time (< 1 day), you are way ahead of most users as to results on this feature