Troop,
The guys who did that diagram are wrong. If I ordered 1/4 sawn oak from them and they cut it like their diagram, I would be returning 1/2 of the wood. With oak especially there will be a big difference between the look of rift and quartersawn wood. I know I am just one guy and they are probably a big company. But I'll say it again, they are wrong. Later today I will find diagrams to show how it is supposed to be cut. What they call riftsawn is close to correct quarter sawing, but if they cut it the way they show it would be retarded and would be tons of waste. Sorry if I am making a big deal about this. It's like the experts that say burls are caused by bugs or injuries.