My impression is that Jobst Brandt's arguments about poorer grip and rolling resistance with "tread" were against the bigger knobs seen on MTB tires and the chunky block tread on some road tires, not the file treads that we're discussing here.
Some quotes:
"I have ridden nothing but Slick or effectively slick tires since the days when only tubulars were available in high pressure tires."
"When Avocet decided to enter the tire market I convinced them to make a smooth tread tire, a slick, because that is essentially what we rode in the days of tubulars, the tread of those tires being about 1/2mm deep when new."
The tubulars he preferred looked like this, of course:
So while he was happiest when Avocet made him completely slick tires, I feel like his arguments in favor of "slicks" apply to our tires with very fine tread patterns, too.