I think you're agreeing with catch23; that 'it' is referring to 'incognito' not 'KISSmetrics technique'. Incognito mode does defeat the ETag tracking (at least across distinct sessions).
I'm not so sure, based on the comment the counterclaim was in reply to. Nonetheless, hopefully these tests better suit the depiction of what we can come to expect from these tracking techniques in mixed session types.