When I learned sawing logs (eastern white pine), it was from an old timer who was using a circular saw.
He would try and square up a cant and then cut boards so when they left the saw they were done.
But he would only saw to the heart/pith and then roll the log/cant over and saw in from the other side, thus reducing the stress in the log hopefully, evenly. And if the log did have stress in it, the last board, known as the dog board as it was the one dogged to the mill carriage, maybe be out of shape. Such as hour glass shaped, thin in the middle thick at the ends or the other way around. And if this board was out of shape it didn't matter much as it was the lowest grade board in the log due to the pith/heart being in it.
If the boards coming off the log did have some round edge to it, he wouldn't completely saw them off the log, he'd saw them until just about to drop off the log, and "gig" back and drag the board back to the log deck. I'd be standing at the tail end of the mill, and he'd grab the board and twist it up from the bottom, breaking the holding grain off the log, with my help. And we'd stack the round edge boards up on the log deck.
Then after he had finished sawing the second side of the cant and the carriage was empty, we'd stack the round edge boards up on carriage in line with the saw so that he could run them down past the saw and cut off the round edge on one side.
Then we'd flip them over and run the other side to a set width.
If he did, by accident, cut off a round edge board and it went down the conveyor belt to the board pit, the pit man would set it aside and it would be brought back to the log deck by the fork lift and re-processed to create square edged boards.
When I saw logs here at my mill, I try and square up a cant that will produce finished boards at the end of the cut. And following the cut to the pith/heart method and then flip over and come in from the other side, as I was taught.
But in doing this, you have to "read" the log and watch for stress. And if you see the boards shifting as you're sawing them you have to adjust your sawing plan based on what you see. Especially sawing hardwoods.