Less metal needed to make the oval plate.
My SupaSwift which has a plain round disc with Victa blades fitted cuts like a completely different mower, so thoroughly and precisely. I enjoy it 3hp Briggs and all.
I have seen the pattern of Victa always engineering to find ways to save per unit cost of production, often with obvious shortcomings like thorough rusting of their steel bases and inferior balance.


Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!