Sublime Chord and Caster Levels

[godryk]

I was checking Complete Arcane and stumbled upon the part that describes Sublime Chord. I find it difficult to understand that bit that tries to explain how to calculate the caster level of your spell. The spanish translation is a little bit ambiguous. The english original is clearer though, but I still fail to fully understand how it works.

I found the following quote on the Internet. I can't tell for sure if this is the original wording:

A Sublime Chord's caster level for both her sublime chord spells and the spells she gains from other arcane spellcasting classes is determined by adding her sublime chord level to her level in another arcane spellcasting class. If she had more than one arcane spellcasting class before becoming a sublime chord, she must choose which to class to add her sublime chord levels for the purpose of determining her sublime chord caster level

So, if I'm playing a Bard 10 / Sublime Chord 8:

Do Bard levels stack with SC levels in order to determine the caster level of the spells gained as a SC? I'm obviously thinking of spells like Disintegrate and the like.

What is the effective caster level for the Bard spells I got in the first levels?
Let's say I cast haste on some allies, how many rounds does it work?

[Toliudar]

In your example, the character casts ALL of their spells as a 18th level caster.

If the build was (for whatever reason) Bard 10/Sorcerer 2/Sublime Chord 8, then (assuming the character added the sublime casting to the Bard casting and not the Sorcerer casting), then they would cast cast bard/sublime chord spells at caster level 18, and sorcerer spells at CL 2.