The majority of the games we play at my site are in the CQB village, so we are generally limited to single shot. But in answer to the topic, i find its quite easy overshoot someone, not on purpose i hasten to add, but most of the time your not firing a single BB to hit someone, so you can have multiple in flight before a hit is called.
The next problem is being hit by multiple people, so you run into a room and the defenders know your coming, you get over killed. Thats a fact of airsoft.
The thing i don't agree with is being hit repeatedly after you have stuck your hand up and shouted "hit, Hit!, HIT!" all that shows is general lack of discipline and disregard for the fellow player, Why that happens is beyond me, we all play airsoft because its the best use of free time known to man, therefore we should respect each other, as we all love the same hobby and that gives us commonality of purpose.