Not cross-cut, not rip-cut, ...the other orientation of bar and chain to the wood. It would be parellel to the pith/ center of rings, resulting in long, stringy, noodly saw chips. This will easily start to clog your clutch cover, if you keep the powerhead up tight to the wood. A more distance from powerhead to the 'round' of wood allows some noodles to fall clear away before wanting to get under the clutch cover.
Noodling is much faster than ripping with a normal cross-cut sharpened chain.
More butt flare in an oak? MIGHT be the nature of some oaks, too, but I don't know. Like how elm has that reversing grain that makes it hard to split and durable in some tool applications such as a wooden axle or hub, IF I recall correctly.