Getting the point to come together accurately isn’t easy. A beam saw gets the shape close, but the chisel and belt sander fine-tune the point.
In the video below, Samurai Carpenter illustrates his technique for beveling the top of a 6x6 post - a detail that is both aesthetically pleasing, and practical as it helps shed water (when properly sealed, of course). Given the variation in dimensioned lumber, it's not an easy detail to get right. His technique involves a beam saw - though he mentions that a miter saw is best. He follows up with a timber framer's chisel, then a belt sander.
Once he gets the top finished he moves on to a tapered chamfer down the post. If you were to look at the detail once it's finished you might think it a highly technical move. But his method proves to be both effortless and flawless.