I don't think he's saying that Ruby handled his job "professionally", just that Ruby was paid to go after Oswald, and that Ruby did not go after and kill Oswald simply because....
I forget - - what do the "magic bullet"/"lone assassin" tin-foilers say was Ruby's reason for killing Oswald? Just because he was mad at him for killing Kennedy? LOL!!
Much was reported about Ruby's background. I for one thought Ruby's reason was B.S.
I am livid to this day that the liberals of that era used the assassination to attack conservative criticism of JFK and liberal feeeeeeeeeeelings claiming that the criticism caused Oswald to kill the President. JFK/LBJ liberals began a campaign of FCC "Fairness Doctrine" complaints that pretty much shut down conservative talk on radio for more than twenty years (until the mid-80s).