Shield spell with (Greater) Spell Focus Abjuration bugs

[sharkinajar]

Two notable bugs I've found with the GSF abjuration change for shield, both of which are fairly impactful:

1. Part of the shield spell sometimes lingers, leaving +4 deflection AC for a turn or two. This seriously messes up your ac, because future castings will not override that extra +4 and leave you with only a few turns of +8 ac until reverting back to +4 ac. This is incredibly painful, because if such happens when you're in the middle of a long fight, you're pretty much screwed of 4 ac.

2. Having equipment with +1 Armor AC (and possibly +1 deflection AC) counts twice against the +8 bonus to AC, causing you to overall only get a +6 increase from the spell.