Bah, apples and oranges. Or a more apt analogy, shotguns and sniper rifles.
The Colossus was meant to jump into the middle of an enemy fleet and obliterate it, yes, yes, we've established that. A dozen times, probably.
More specifically it was meant for situations like the one in Freespace 1, where you fly the captured Dragon. In that situation, the Colossus could probably have wiped out every Shivan vessel in the area without sustaining too much damage, even with beams.
Note that it could've also taken advantage of the Lucifer's forward-facing weapons with its massive broadside armanment.
It didn't work well in Freespace 2 because the enemy vessels changed. Specifically, the Sathanas was introduced. Rather than being a general purpose vessel like most Shivan vessels, the Sathanas is a specific tool. It's configured to shoot forward at big, slow things. The Colossus is a big, slow thing.
Thus, the Sathanas was perfectly configured to take advantage of the Colossus' weakness, while the Colossus' weakness (spread-out rather than concentrated firepower) was perfectly suited to make it ineffective against the Sathanas.
I believe the point Volition was trying to make is that Command was trying to fight the last battle - they were using tactics/strategies they'd learned to be effective in the last war against the Shivans, rather than coming up with new ones.
Consider the difference in weapons and ship assignments in Freespace 1 and 2. In Freespace 1, weapons and ships are invented out of desperation. In Freespace 2, weapons and ships are pretty static; you're simply given access to them.
Meanwhile, the GTVA is getting totally reemed. The only person trying something new and coming up with new technology is Bosch.
It's basically the exact opposite of FS1.
But I digress, by a rather huge amount.
