I don't understand how even having a 20% detection rate isn't better than 0%. Am I missing something? Are there a lot of viruses popping over the net that even the 20% detection is already too late?
It's all a bit moot though as before this happened, McAfee was probably worse than anything a PC can get infected with. Now it's gone and proved it beyond any doubt.
Think of it in another way, at any point in time you have x number of virus that you are likely to come across through whatever means. If all those viruses are in the 0.2%, then the catch rate isn't going to be 99.8% it's going to be 0%.
So being able to catch 99.8% of 3 millions viruses when new ones are released all the time is a pointless comparison for efficiency.