I do have to think constantly about what my character would think or do in a given situation based on his personality let alone his knowledge (like did was he there for that exposition or did he only over hear it at the table, should I be able to use maths or a lever to try to solve a problem. Does my backstory as a 200 year old soldier let me know about trolls vulnerabilities?
This means that like [MENTION=97077]iserith[/MENTION] I tend not to bother. I try not to "spoil" monsters for the many newer players I play with even if it lead to fraught fights with paralysing ghouls or whatever but I don't sweat bringing acid & fire if I know that we're facing trolls.
Which is fine. Everyone has different strengths and weaknesses. What I find easy, you may not. What you find easy, I may not.
Of course I forgot I had drifted away from the D&D boards. D&D is terrible at doing realism - your 18 wheeler argument falls down if PCs can take a dragon that's even bigger to the face.
Which is only really true if realism is a dichotomy. It isn't a dichotomy, though. Rather it's a spectrum with utter reality on one end and absolute chaos on the other end. D&D falls closer to the realism end than it does the chaos end. It has rules that try to model reality to a degree. Swords that are edged, arrows and spears puncture, falls hurt, etc. The game reality also explains how magic and dragons make sense, so I accept those things. Some things are unrealistic but must be accepted in order for the game to function. Combat I'm looking at you on that one.
With the above, I accept X level of unrealistic, but that doesn't meant that X+1 is okay. When I get to Iserith's level, it's more like X+1000, which is intolerable for me. That I'm okay with magic and dragons doesn't in any way mean that I have to be okay with everything unrealistic.
How do you judge realistic - by making in game comparisons or by using out of game logic?
I'm not sure what you mean by in-game comparisons. Would you elaborate on that?
I appreciate this too. I buy immersion. Personally I am happy with strong colour but I would rather enjoy things that do not jar with the tropes or genre that I am playing in. I feel the best way to avoid the coincidences is to avoid creating the situations where they are pertinent.
You can rationalise most any weird circumstance in a high fantasy game but I would rather not have to.
For me, it needs to make sense with the PC in question. Going back to troll weakness (of course

), if a PC grew up near the troll moors, I wouldn't even make him roll. He would just know. A PC from far away that had some knowledge of swamps or monsters would get a fairly easy roll. A PC from the desert where trolls just don't ever go and with no background to indicate possible knowledge would not know or get a roll. I don't buy the "I overheard it in a tavern" justification.