I found new facts for the force field argument debate.
It is thought by Elfangor in the Andalite Chronicles that the Jahar is well-shielded, and as anyone who's the read book knows, the Jahar is an Andalite fighter, Alloran's personal fighter, but a fighter nonetheless, showing that Andalites CAN and DO shield their fighters. So the Yeerks, who have stolen technology from them, can probably do the same. YET IT NEVER LOOKS LIKE IT!
In #1. The Invasion, Elfangor's fighter and a Bug ship blow each other up without encountering force fields.
In #2. The Visitor, "a bulldozer going nine miles per hour caused one of these things to explode!" to quote poparena.
In #11. The Forgotten the shockwaves from the laser explosion caused the ships to crash. No mention of force fields.
In #18. The Decision several low-flying Yeerk and Andalite ships are blown apart. Still no mention of force fields.
In #25. The Extreme the Blade ship blows up the Bug fighter. Force fields are not mentioned once, though somewhat justified.
In #30. The Reunion I think a few Bug fighters are destroyed by the Empire ship. Once again, force fields are not present.
In #34. The Prophecy the Andalites in a Bug fighter destroy another Bug fighter to aid an Andalite ship. ONCE AGAIN, FORCE FIELDS SEEM TO BE A FOREIGN CONCEPT! Are ALL ships unshielded despite the fact that their pilots claim that they have shields? WHAT IS THE LOGIC HERE?
I could go on and on, but... you get the point.