On Page 3 of The Wars of Reaving Supplemental, in the Society Unit Definition Chart, BattleMech and vehicle units are listed as having a -1 roll modifier when rolling on the Random Skills Table (TW p. 273). Is this applied additively to the existing +2 (BattleMech) and -2 (vehicle) modifiers for Clan forces?
So, in other words, do Society BattleMech units have a +1 modifier, and vehicle units a -3 modifier, or do both simply have a flat -1 modifier?