[Taxacom] Usefulness vs. convenience (Protista)

[Kleo Pullin]

I have a few questions about this discussion:
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1. Why/how/for what?is Protista more useful or convenient?
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2. And what is the difference between usefulness and convenience--this thread is titled "Usefulness vs. convenience?"

>>??????? As for rhodophytes (and glaucophytes),
Cavalier-Smith includes them in a very broad Kingdom Plantae. Others
have left them in Protista, but included green algae in Plantae (making
it equivalent to Viridiplantae). 
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3. Who has left?rhodophyta in the Protista?
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Thanks,
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Kleo Pullin