I don't believe that was the poster's intent. If they would have said instead, "Thorson is one of the reasons we are winning.", would that have carried the same connotation?
A great leader identifies and surrounds themselves with great people. They establish a vision. Then they empower those people, clear roadblocks and get the hell out of the way. Speaking highly of an assistant by no means diminishes the head coach. If anything it reinforces what the eye test has already revealed - the signs of a great, young head coach emerging in front of us in real time. His ability to assemble a solid coaching staff, build a team from scratch and have them ready to play fundamentally sound, inspired basketball in the span of several months speaks volumes to his potential. I am so excited for the future of Gopher basketball.
Message boards, like email, are notoriously unreliable for putting things into context. The most likely explanation is the poster was just excited with the team and loves their defensive intensity. Since most people tend to write like they talk, they just blurted it out as if they were in a live conversation. Upon hearing it, you could have asked them what they meant by that instead of jumping to conclusions. If you still feel it was somehow racially motivated and a slight at HC Johnson, then you are entitled to feel that way, but I don't believe that was the intention.