Can Quicken Spell be used spontaneously if Rapid Metamagic is used?

Question

The Quicken Spell feat carries this special requirement:

This feat can't be applied to any spell cast spontaneously (including sorcerer spells, bard spells, and cleric or druid spells cast spontaneously), since applying a metamagic feat to a spontaneously cast spell automatically increases the casting time to a full-round action.

This is in reference to this rule in the Metamagic SRD:

Therefore, such a character must also take more time to cast a metamagic spell (one enhanced by a metamagic feat) than he does to cast a regular spell. If the spell’s normal casting time is 1 standard action, casting a metamagic version is a full-round action for a sorcerer or bard.

However Rapid Metamagic specifically supersedes this rule:

When you apply a metamagic feat to a spontaneously cast spell, the spell takes only its normal casting time.

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So...

Can Quicken Spell be used spontaneously if the casting time is reduced by Rapid Metamagic?

The way I read it, Quicken Spell's special is more of an answer to a logistical question, rather than an explicit prohibition, given that it sites another effect(the spontaneous spell's increased casting time)as the reason for disallowing it. I see it similar to if the PHB said, "You can't wield three weapons since all playable races have only have two hands." If you somehow gained a third hand, the rule would cease to apply.

Answer 1

You are right. The 'since' in the first quote implies causality: you can't quicken spontaneously cast spells precisely and explicitly because the casting time increases.

From the moment you got Rapid Metamagic, the casting time increases no more and Quicken Spell can apply.

Answer 2

Yes it works

There's also the alternative class feature for the sorcerer: Metamagic specialist (PHBII p.60) that confirms this works by RAW:

Benefit: You can apply metamagic feats that you know to sorcerer spells without increasing the casting time. This benefit even lets you quicken your sorcerer spells with the Quicken Spell feat.

Since the benefit is exactly the same, it works with rapid metamagic too.