Keep in mind, the biggest advantage of striking often in several locations is to keep your enemy off guard. This is essentially your "defense."
Additionally, such actions really help to hide your true intentions. If you only amass one large fleet one hop away from your target... every time... your opponent is going to know where you are going.
However, if you have several smaller fleets all over the front lines and then maybe a stronger, "invading" fleet a few hops back into your terrority, it can really keep your opponent guessing.
In the scenario described above, wait until he commits his force to one of your attacks, then send your attack fleet to support your "skirmish" fleet that is furthest from the action. Your attack plans don't always have to be so static, they can be dynamic, where you are taking targets of opportunity as they present themselves, not forcing yourself into the same choke-point again and again.
The whole point of strategy is being able to adapt it on a moments notice. If you try to make your opponent fit into your strategy all the time, you'll get in trouble. A lot of times, you must be able to adapt to his play-style.