HR people new to an organization have a double whammy of hazards. First of all figuring out the plethora of new processes and ways of doing things is difficult. In addition the hows and why's are an unknown. Everyone would like to think they are a No BS HR person who uses a machete to cut through red tape . But every organization has their own politics and drama. Sometimes it is very hard to figure out the dramatics (also paranoids or people who view risk takers as some sort of leper) from the people who are just trying to help you out ("You know the COO is the approval authority for that and he is specifically looking for..."). Until you figure the political atmosphere out you have two choices:
1. Take refuge in the protective embrace of corporate HR and become the operational spy that narcs and circumvents your operational leaders at every turn.
2. Trust your operations guys and go along for the ride, make mistakes learn (maybe get thrown under the bus), but learn with your operations guys (you know the guys that actually make stuff and drive profit) and hopefully bond with them to create a solid relationship for the future.
Of course I choose #2. I see no problem going on an early ill advised jihad against corporate with your operations guys support, even if you know you will lose. It is call team building people and OPS guys need to know that you are no pansy that you wont be the one to constantly nag and harass them out of any out of the box idea they try to implement. Once they see you don't mind bleeding a little for them you would be amazed at the respect you get from them. This you can cash in later when you are coaching them to have more patience before they terminate that person who hasn't had a below average performance evaluation in his life and no write ups in his file ("Don't you think you should tell him what he is doing wrong in a formal setting before termination?").
I have always been an all or nothing type of guy and, in the end, I don't mind sacrificing a little bit of my early credibility with the corporate types to solidify my position within my team of people who actually drive profit.
So my advice, be prepared to bleed a little or go home.