I haven't totally scoped Johnny out, however, I think Pernell probably has enough to deal with him, albeit barely.
Without disparaging Whitaker, Bratton fought a much richer bunch of opponents as a WW...He had everything, speed beautiful boxer, combination puncher, great courage in the ring, but he had trouble with his fractured jaw several times...But when healthy I think he out flurries Whitaker... He was beautiful to watch, was JB...
Hard fight for Whitaker. Bratton had quick hands, a good reach, decent power too. He usually got the better of the boxer types he faced, as wins against Willie Joyce, Bobby Dykes, Del Flanangan testify. It was more the brutes that got the better of him, not the boxer types. That said, Bernard Docusen turned the trick, so it is by no means impossible for Whitaker... Like the De la Hoya - Whitaker fight, it might come down to what you like better, Bratton's harder shots and flurries, or Whitaker's accuracy with the jab and defensive artistry. Knowing me, I'd edge it for Whitaker.