<p>I haven't seen Sherlock, but if a villain's redeeming quality is in any ambiguoius, then it's a very weak argument against them. Looking at the first discussion on Roger, it was pointed out that he was never explicitly confirmed to feel remorse, and given everything we know about him it's highly unlikely. Even if you assume he felt remorse in spite of that, it would count as offscreen due to not being confirmed. And since offscreen villainy doesn't count in a character's favour, an offscreen redeeming quality shouldn't count against them.</p>