(the obvious incentivisation is that oil companies need to hire country managers who are wealthy enough on their own account they can assume any necessary irregular payments and entertainment will be arranged by their personal lawyers, or in any case, well off the companies' own books?)
Incidentally, Berdimuhamedow's thesis was
"Clinical features and pathogenesis of major dental diseases in children of multiparous women", but I haven't bothered to look up his advisor.