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Yes, I got another approach from Yuri, pasted below. Please let me know if you need furthur info.
The closest analog of a FIXED LOD dimension field
(in the Pre-LOD era of 8.x) is a Conditional Set.
Your [Sales Decider] logic is used to build a Condition.
And the VizLOD granularity of Product ID / City / Year
is used as the Set member Dimensions (via concatenation).
The resulting Set allows to avoid the [Sales Decider]
Discrete Aggregate's Ignore in Table Calculations trap.
Please find the attached.