After having just unlocked the 36 point skill "Mine Tracking" in the economist tree, i noticed that the talent is currently quite the downgrade for (medium) mine effectiveness.
The skill changes mines into projectiles, and doing so removes the proximity fuse from the mines. The effect is that - previously - mines would detonate when an enemy was fairly close to them. After changing them into a projectile, the mine has to specifically touch the enemy's centre to detonate (Touching the sprite alone isn't sufficient).
As the mine has a very low speed of 50 at skill rank 1 it is essentially impossible to hit anything with the talent taken; even the slowest enemies can just evade the mine entirely. I suspect that this isn't intentional - and that the mine should have kept its proximity detonation. (Or perhaps that medium mines weren't taken into consideration, seeing that the heavy mines are manually detonated).
Savegame and Character files
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