Oh Jesus where do I start.
One if you ribs are not tender and you are using higher temps (260 and above) you simply are doing them right. Maybe you are pulling them off to early or whatever. I will say this... some pits I can do 325, some 270 (like both my Brazos Pit and the Meat Mama) but and both without foil... I have to watch out or I will have fall off the bone tender.... so any thought that hotter and faster cannot give tender results is simply the cooks fault or the gear or both.
Two, whoever said there is not done time difference between 300 and 225 is dead wrong. My weep ribs are done sooner than other people's ribs even without steaming them in foil. Low is def a different process than high but there is a huge time difference. I can imagine a famous cook saying something like "some people do 'em at 225 and some people do them at 350 but if ya want good ribs they take 5-7 hours." The quote may not mean they are equal in done times but probably he thinks that to get what he thinks are good ribs you have to cook them 5+ hours.
Weeping Rib Method above 260 degrees
http://www.youtube.com/user/PopdaddysBBQ#p/u/2/GbBFZstQRUY