Having completed the story with Strelok's ending, there's still something I don't understand [spoilers]

I don't fully understand Strelok's motivation behind asking Skif to kill the Doc. When he played the recording of prof. Kaymanov talking to the C-Con members when he declined to enter the pod, he talked about their discoveries being used for betterment of all mankind. While I understand how this is contrary to what Strelok wants with the zone, why does this cause Strelok to want the Doc dead? Other than sitting in his bubble or going around healing people, the Doc doesnt actually do much in the zone. He doesn't seem to want to affect the situation within the zone - his involvmenet with Strider and Orbita was only spurred on because of Skif, not of his own initiative. As such, I don't see how Strelok could see the Doc as someone that needs to be killed.