by Lyr » 24 Nov 2012, 06:23
There are some fine distinctions to be made between the two.
1. Score: Destroying any of your units IIRC will decrease your score. Often players will look to their score, especially later in the game to measure their strength compared to yours. Lowering your score could, theoretically provide your opponent with an incentive to launch an offensive against ou on the ground, or it coud also provide an impetus for them to try and develop an advantage in another area, e.g T3 Air. It comes down to whether you want to appear weak, or strong to your opponent. Purely a psychological dis/advantage.
2. Resources: Engineers will reclaim the factory through it's own health and then reclaim through the wreck. Do you need/want the mass right now. For example if you are just wanting to pour that mass into a T3 mex, or experimental, it's better to Ctrl-K and pick up all the mass straight away. If you however, are close to full storage but are streamlining your economy, then perhaps just straight reclaiming might be better.
Conclusion: It's probably better to just CTRL - K and draw up the mass faster. The only otherwise situations are when you don't need or have the build power to apply that mass straight away.