Yes indeed but didn't Portal have to eventually directly order Harris to cooperate with the Americans on attacking German oil and transport facilities, which he hadn't been keen to do?
One biographer perceptively said that Harris would never disobey a direct order, but would argue like hell up to the moment it was issued. Once given the order, he would execute it faithfully - often exceeding the original intention. A classic example was the transportation attacks in the run-up to D-Day. Harris had to be ordered to make them, but once ordered he put much in more frequent and more accurate attacks than required.
It's also interesting that Harris also stated that the only senior commander he never resented taking orders from was Eisenhower. He came under Ike's command for several months before and after D-Day and reckoned he was never so ably strategically directed.
[Eisenhower's air commander was Tedder, who believed strategic bombing should be woven into an overall strategy].
Harris and Eisenhower maintained a warm friendship for the rest of their lives.