Pilotbear,
Whopity has posted the link to the Notes To Candidates document. Paragraph 3.6.7 states:
The examiner will deny the use of any aid that would allow the applicant to track directly to the diversion destination.
I agree with your points in "real life", but in real life it's quite possible (and likely, in fact) that there will be no navaid at the destination, thus denying the "most efficient way" of doing things. On test the examiners want to simulate the more difficult scenario, so if there happens to be a navaid at the destination, or almost directly en route, the examiner will deny you the use of it.
FFF
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