Dual classed fighters and weapon proficiencies

Pingwin

Can anyone clarify how exactly weapon proficiencies work when dual classing from and to fighter classes?

If I dual class from a fighter to say a thief, can the thief put more than one pip into a weapon? Am I limited to specialization like multiclass fighters or can I go to grand mastery? Also do I need to wait for the fighter abilities to reactivate before I can start putting more than one pip into a weapon?

If dual classing to a fighter, are there any restrictions or can I get to grand mastery?

jmerry

Your dual-classed fighter-thief can put only one pip into a proficiency as long as the dual is incomplete. Once the fighter class is active again, they can put as many pips as a fighter of the same level could; 3 if their level is 3 to 5, 4 if it's 6 to 8, or 5 if it's 9 or more.

If dual-classing to a fighter, it doesn't matter whether the dual is complete. Only your fighter level matters in that case, so you can achieve grandmastery if your fighter level is 9 or more. This is, of course, impossible under the TotSC experience cap of 161K.