Wood – Are Record and Stanley brand smoothing plane blades interchangeable

Like you, I find it more effective as a cutter through harder surfaces if you move the blade across the surface you wish to cut. I also apply light pressure to the tool while "sawing" with it.

Although in your case, it probably was simply that the wood was very hard.

The difference between a 10" 60T and 80T saw blade is only slightly noticeable. In practice, chip out with either isn't a huge concern, provided you go slow. An 80T blade is naturally going to slow you down more, so that may be useful if your tendency is to yank the radial arm down and go.

Another consideration is the end grain of the piece, some trees are just flakier than others, in that case an 80T is a safer bet.

Teeth aren't the whole story. If you throw a crosscut table blade on a miter saw it might have a tendency to feed faster than you want. If you get a miter blade then there's not a ton of difference. The miter saw blade teeth are back angled a bit to avoid pulling the arm in on you.

So the safe bet is the 80T miter blade, but I'd be surprised if a 60T gave you any trouble.