If I have noble attempts landing over a 10 minute period, I will try to snipe with the villages own troops as well as setting up other snipes, increasing my own chances of getting a successful snipe, especially if the trains are tight. (300 ms trains are a bit easy, but we won't go into this- too player dependent.) However, it gives you more sniping attempts.
If I have 100 trains landing in the same second, I obviously can only get so many of them in the period they land with that type of sniping.
Also, if there is a 10 minute gap, as long as your village is within a 3x3 of the village with your paladin in, you can get an extra stack moved (assuming it survives whatever hit it takes) and that's one less village taken. (You could obviously move the paladin before hand).
All circumstantial Adam, but circumstances do count for a lot in this game.
Not to mention, as you said, the psychological effect it has. Especially on the defender. It's much easier to win a difficult war by breaking the defender then it is to keep attacking until you gain a significant enough lead to just keep on battering through.
If I see that for instance, Tribe X has taken out 4 players, with 20 villages each, all within seconds of each other, whether or not the gap made a difference physically, it's going to affect my morale when fighting said enemy. Those who are tight with their landing times appear to be stronger as well. Whether they are actually or not is overshadowed by the reputation that proceeds them.
