@Chess Pwn,
per your reasoning spell combat would not work with multiple attacks with the first-hand weapon for BAB>5 reason.
Hands up who disagrees on that, please.
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@ Komoda, this is not comparable, as
1) the off-hand could be free for casting per the latest FAQ on FoB with a single one-handed Weapon.
2) the feat only reduces penalties for an attack action everybody can do being armed in each hand, and armor spikes are not a wepaon associated with any hand.