Being a HiPo does guarantee that you will be ranked high.
I was told by my department manager that there was no way for me to improve my ranking any higher because the next level were all HiPos that had to be placed in the top category for political reasons.
My boss’s boss said that I was lucky to be ranked as high as I was because if there were more HiPos that I would have been moved downward in ranking to make room for them.
Forced ranking with politics, sponsorship, favoritism, and HR Race based adjustments is causing massive attrition of productive employees and promotion of id--ts.