Saben,
As you know, there are more ways to get tech than just boarding a ship.
Plus every defensive measure you put on a ship requires space and research points. The problem with specialization is that you limit your ability to surprise the enemy. A balanced task force will survive longer and gain in the long run.
I've seen this kind of "rush" idea in other games and there is always a way (usually many) to counter it. MM has built a balanced game, allowing for many play styles to work extremely well. But I think "history" will show a balanced research approach will over come a single weapon focus one.