I thought the rollers helped reduce friction and heat?
99-44/100% of SBF timing chains are "roller chain". This is a chain with a cylindrical roller mounted on the link pin. This is where you get friction reduction over a plain "link chain".
Unfortunately, many folks...including manufacturers, have come to call "double row" roller chains "double roller", meaning chains with two rows and sprockets to match, with two parallel toothed wheels.
Double the chain, double the teeth, double the friction.