Apostacy on mindless lifeless constructs?

[Excist]

My conclusion from the above is that it was originally supposed to be MR resists easily ( -4 to penetration) because it requires no research and single path and usually targets the most valuable units.

Apparently CBM has gone overboard in "balancing it" and it now works as often as charm, but with a more common spell path, lesser research requirements and zero fatigue.