Gerald,
Your understand of PCS scenes is correct. Additionally, C2 could have a very fast ramp rate while C3 has a very slow one, etc.
With the Pronto and IR543 you can do all 16 unit codes on a single house code. If you had a non-touchscreen universal remote you'd be limited to unit codes 1-10 as that's all the remote manufacturers have programmed into the remotes. You could learn units 11-16 into a learning remote but you'd have to have access to one of the touchscreen remotes (Pronto, RTI T2, etc.) with which to teach it.
I'm glad you like the site, I worked a bit on it last night and hope to get more done today. As always, I need as many proof readers as I can get as well as comments on what is explained well and what might still be a bit confusing.
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