First, absent confirmation, the presence of perchlorate at the Phoenix site is speculative. But even if it is confirmed, it will not necessarily support Oyama's hypothesis.

Oyama basically proposed that the Viking samples were sterile, no biology whatsoever, and that the mimicry of biology found at both Viking sites was due to an elaborate chemical sequence that relied on ultraviolet light acting on the atmosphere, the atmosphere acting on the surface "soil", and the water vapor of the Viking tests forcing reactions mimicking biology when in contact with the highly oxidized and oxidizing "soil," oxides and superoxides which, conveniently, served to sterilize the "soil," consuming every trace of organic compounds that should be there in abundance simply through the agency of carbonaceous meteorite bombardment.

Perchlorates were not -- and are not -- part of Oyama's suite of oxides and superoxides that must be there for Oyama's hypothesis to stand. And in fact, as Robert Clark's posts have indicated, perchlorates are not the sterilizing oxides/superoxides of Oyama's proposal. Far from it. Perchlorates, if that is what has been found, in fact are quite capable of sustaining biology on Earth, and who knows, might be able to do so on Mars.

Oyama came up with an intricate mechanism to explain enigmatic Viking results that may well have had a much simpler explanation. Occam, razors, and all that. There will be all kinds of efforts to pack any new findings into Oyama's overall hypothesis, and some of it might work for a while, but simpler and simpler explanations are bound to emerge. (There's always hope!).

We're still waiting for any confirmation of Oyama's oxides and superoxides. Those are the ones that are required for the biological mimicry the Vikings found that he's accounting for. Perchlorates aren't gonna do it.