In "Balance of Terror", the Romulan ship attacked Earth outposts using a plasma ring projectile weapon. This weapon could chase the Enterprise at maximum warp speed, overtake the ship, and still cause damage even at the edge of its effective range. The weapon penetrated a mile deep inside an asteroid made of solid iron, according to Commander Hanson on Earth Outpost 4.
After "Balance", this fearsome Romulan super-weapon was seen again in "The Deadly Years", but seemed to loose its effectiveness. The Enterprise sustained several direct hits, but was nowhere near as overwhelmed as what was clearly seen in "Balance". After "Deadly", the super-weapon vanished altogether.
By TNG, the Romulans were using photon torpedos. Granted, the plasma weapon was never seen again in TOS either, but doesn't it seem that the Romulans were defanged? How can this apparent step backward be explained?
After "Balance", this fearsome Romulan super-weapon was seen again in "The Deadly Years", but seemed to loose its effectiveness. The Enterprise sustained several direct hits, but was nowhere near as overwhelmed as what was clearly seen in "Balance". After "Deadly", the super-weapon vanished altogether.
By TNG, the Romulans were using photon torpedos. Granted, the plasma weapon was never seen again in TOS either, but doesn't it seem that the Romulans were defanged? How can this apparent step backward be explained?