Why don't you call Sekonic support and ask the question?

Every time I called, the reps were knowledgeable, patient, and willing to answer questions. They don't care if you own the product or not. (they don't even ask)

As far as I know, it's all in the matter of calibration. I can understand your concern over oblique lighting but unless you are talking about extreme angles, I don't really see it being an issue. The dome does not retract that far and the diameter of the rim is such that it only obscure the dome extreme cases. Plus, the purpose of the dome is diffusion....