Ok,maybe US oak is proccesed with a better way thats way it seems softer to me.Im a carpenter in proffesion,i bought in 2003 2,5 cubic meters of US quartersawn oak for 3400 euro(each c.m.),usualy i get that amount of eu(bulgarian or whatever)for 1.600 euro(each c.m.) but not quarter sawn.That EU oak seems to be a lot denser,HEAVYER and hard to work with in the machines..Also,i wood that i bought about a year ago was filled with small cracks,and when i picked it up it seemed JUST fine..My bandsaw that is a bit biig you can feel that its loosing RPM when slicing that EU wood(5cm[2"]cut),unforunately have to work with because noone is paying for US oak..I mean that this US oak that i worked with was walking so fast in the bandsaw as almost as mahogany...Now the euro one i give you small very possibilities to see that...
Sure i dont doubt the facts that you read and i read about how dense or hard a wood is,but when it comes to bandsaw plane wrasp etc tones of wood(aka in action) i think that you will notice what i say.
It seems odd but still reality,please dont think that i try to say something diff. to play the "smart" one,its just what i see when i work with them,and ive worked tones of those wood species.
Peace