Yes I am aware AMD does not recommend it, that is obviously because they do not want any of the grease's disadvantages appearing and causing more failures.
The pad is safe to use as you have nothing to really do other than just peel off the protection tape.
However while I am aware of the grease waste over time, I've yet to hear anyone here complaining. If anything, Intel and AMD actually will sometimes ship retail CPUs with grease. I don't know if it contradicts their recommendations, or how it's handled but I do remember seeing the instructions booklet showing diverse Retail CPU installation instructions for either a pad or thermal grease that shipped with the retail box.
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