Movement question

[aspiringlich]

How would you adjudicate something like this:

The PCs are all engaged in melee with a bunch of bandits. You the DM decide (prior to initiative) that a seriously wounded bandit will attempt a fighting withdrawal away from the PC fighter, and the player running that fighter declares that he will make another melee attack and try to finish the bandit off. The bandits win initiative, and the wounded bandit backs away from the fighter at half-speed.

Here's my question: will you allow the PC a movement in order to re-engage the bandit in melee, even though he didn't declare any intention to move during the declaration phase? I think the common sense answer is, of course you allow it. It would be ridiculous to say that the fighter has to stand there stupidly while his opponent is backing away. On the other hand, that does mean that players (and monsters) can re-calibrate their actions mid-round, which seems to violate the rule that all actions have to be declared prior to initiative.

I raised this question over on DF in the Classic D&D forum, but it was pointed out that my assumption that all actions have to be declared prior to the initiative roll isn't to be found in the B/X rules. Since it is in the LL rules, it seems an appropriate topic to raise here.

[bighara]

I don't use the declaration phases myself, so in my case the fighter could follow.

If you do declare first, then one might argue that the bandit gets away (for the moment) because that's one of the advantages of winning initiative. The idea is that things are really sort of happening all at once anyway.

On the other hand, a trained fighter might be considered capable of adjusting his tactics as the situation develops. Just be consistent in your rulings and you'll be fine.