Old D&D and D&D3E/4E treat initiative and combat order differently like so:
D&D 3.5 / 4E: All participants roll individual initiative, once only at the start of combat. Each player takes all of his combat options on his own turn. No morale rules.
Basic D&D / Labyrinth Lord: Each side declares its actions ahead of time, then rolls group initiative, at the start of each round. Each side, as a group, makes all their movement at once, then ranged, spells, and finally melee, before the next side gets their actions. Morale has monsters roll to flee when the first ally is killed and when half their number are killed.
How does the difference affect combat? What are the advantages and disadvantages of the oldschool system? Is combat faster or slower under the old system, or is it more or less difficult to keep everything in order?
Best Answer
Combat in the old-school systems is immensely faster. Yes, there are also fewer interdependencies between actions than in WotC-era editions, which reduces the amount of tactical wrangling over what each player should do; but even apart from a simpler choice of actions, everyone taking actions at once just vastly simplifies the process of getting the round done.
Having players all take their turns together simplifies the planning of the round. Because order of the players' actions when moving or attacking isn't a rule-bound thing, it's easy and comfortable to declare an action, realise it's a bad idea, and quickly roll that back to do something else. Getting everyone's actions to work together cleanly is just a much simpler process due to the flexibility of moving all at once. Even in a tactically-complicated round where people are thinking hard on the best way to execute things, even one where people are declaring actions and then rolling them back because they suddenly see a better alternative, the rounds are quick and there are few mental, logistical, or rules barriers to moving the action along at a brisk pace.
Since the players are all going pretty much together, they don't tend to "check out" and stop paying attention to the round. The gain in speed from not having to remind the next player that it's their turn, and not having to repeat everything that just happened to get them up-to-speed, is not inconsiderable.
Keeping things in order is actually simpler because there is less to the mental model the players have to individually retain and collectively synchronise. You just don't have to keep track of turn order or think about who should do what when on which turn to make a tactic work. There are no wait actions, no triggers, no finicky positioning work to make sure people are in the right place when someone casts a certain spell three initiative-turns later in the round.