Ok, I'll keep this going and toss in my 2 cents worth.
Dig a hole 6 inches deeper than you need.
Add 6 inches of gravel.
Pound it down with a fence post.
Add more to bring you back to 6 inches. Repeat as necessary.
Double wrap the bottom of the post with Grace ice and water barrier. This stuff sticks to wood like super glue. Finish the wrap a couple inches above ground level. Do no seal the bottom of the post, the long grain end. Water entering through the top, and to a lesser degree, the sides, eventually migrates to the bottom. Think of a piece of wood as a handful of plastic straws mashed together. Pour water on the top and eventually some comes out the bottom.
Add cement and slope away from the post. Yeah, cement wicks water. Not an issue.
How does this work? The gravel allows excess water to drain away.
The rubber (high density cross laminated polyethylene) keeps water, oxygen and microbes off the wood surface. This stuff is rot resistant like you wouldn't believe.
Your post wont rot and you don't need to spend extra cash on fancy plastic post anchors/protectors.
Oh yeah, frost heaves.
Smooth, regular surfaces will not frost heave. A post buried below the frost line will not heave.
Adding cement with irregular surfaces above the frost line will heave. Just a fraction then it will try to settle. But when it heaves, small amounts of dirt get under the post stopping the settling.
If frost heaving is a big issue in your area, set the post in a large diameter concrete form tube. Then add concrete.