Purely out-of-character (OOC) posts should be put in the signups (since we don’t have an OOC PM or any other sort of discussion topics). For future reference, it’s okay to have a post with OOC comments as long as you also post something in-character (IC). Example:
As to actually answer your question, most RPs leave it as a judgement call to the player. If you think your character can dodge, block, or otherwise respond to the attack, you have them do so. If not, you detail how the attack affects you. Granted, that leaves it as an individual responsibility to not have your character dodge every attack and be realistic and fair about how the fight progresses.