These calculated times are always about "what if". Personally I think that it's better to avoid and if possible give drivers, who are in direct fight, same notional time. The situation when it's needed is very rare and while we can say that it's unfair for the one who already finished and could have won some time we can say the same about calculated time loss for the other. You simply can not know what would have happened in the rest of the stage. That's why I think it's better to avoid any such calculation (generally speaking - of course in this particular case when we know that Ogier had a puncture it's impossible that he could have taken some time back).