I'm a fresh new player of Pathfinder, thanks to a coworker of mine who's basically my hero at this point for ending my search for a local RPG to join!
Anyway, we're one session in using the Starter Kit and it's going great, I'm getting into my Rogue character really well, cold and calculating and not above stealing some of the loot before the rest of the party notices! (Hey, palming that Ring of Protection saved my life when the +1AC let me avoid a powerful attack!)
But yeah... calculating. While the rest of the party were content with "Well, that Goblin has been hit already, so I'm going to try and finish it", I find myself thinking "let's see... that last Goblin took X damage before being killed, this one has taken Y damage so far... if I move to flank then I might be able to inflict X-Y damage and finish it..."
Does mathing damage calculation like this come under metagaming? Or is it fair for a Rogue to make such calculated movements in battle? Is it even reliable to count HP like this?