We could also note that in Alis time, Dezolis wasn't populated by alot of Palmans.
You also have what the eclipse torch does to Laconia..
Eclipse Torch (I, IV [mentioned in II as well])
Once every thousand years, Ryucross draws near to and completely eclipses Motabia. On that day, magic energy from the sleeping spirits of Algol and Ryucross is emitted towards Dezolis, where it is gathered in and filtered through the Aeroprism, irradiating Laconia with a pale green light.
This flame is said to burn until it is extinguished in the next eclipse in 1,000 years' time. It does not emit heat, but the blessing of its light will heal frostbite from any living thing that holds it. Moreover, it will also "draw out" the bearer's true colors and bring to light whether the bearer is "good" or "evil".
Now.. The Eclipse torch bathes Laconia in a special glow through the aeroprism and since Alisa had the aeroprism..
That is why Lashiec feared it. Laconia's properties when bathed by the eclipse torch.
Back in the time of PS 1 with all the religion, the way to show Lashiec was evil was to bring out his true colors. Hence the Laconian Sword..
Then we have PS 1 script:
Arms made of laconia conceal holy power. Lassic fears this power and has been running and hiding in different places in the planets of the Algol System.
Alis also has to get the aeroprism and hold it up..
Now let's go jap PS 1 and we find a mistranslation in english xd Lashiec hid the weapons, not himself.
What? ‘Overthrow LaShiec?’ If you really are going to do that, you must gatherall of the Laconian weapons: Sword, Axe, Shield, and Armor. These weapons are more powerful than any others. I’ll be praying for your safety.
- Weapons made from laconia conceal holy powers, y’know. I heard that LaShiec despises them, so he hid them here and there throughout the planets of Algol.
~Don’t let this get out, but there's a fortuneteller named Damoa who is in posession of a crystal that LaShiec hates. There must be something secret about that crystal.
~It’s ‘Laconia’! Laconian weapons are the strongest [in the solar system].
So my geuss is Laconian weapons in PS 1 have Holy Powers since they are rare and it comes from the Eclipse torch.
Come PS IV.. there is no more churches in Algo so HOLY weapons aren't needed?
Unpure Laconia makes Silver weapons in PS IV, Pure Laconia makes Laconian weapons. Neither is blessed with holy power? Also.. Reflectmail is only on Dezo and it doesn't really help cut down tech damage xd