VF> Main question: how much of a performance & efficiency
VF> difference is there when you get a set of shoes/pedals?
The efficiency comes from attaching your feet to the pedals and it's a 
tremendous gain.  You can do this with toe straps and clips.  Going clipless 
simply makes it very convenient to get in and out, that's all.
VF> I'm wondering about the upstroke side of things, since the knee
VF> joint isn't really designed for much upward pulling... what
VF> change in muscle use is there? Is it vast?
No, there's no "pull" per se.  The efficiency comes from being able to spin 
quickly without losing the pedals.  I try to push forward as my foot goes 
over the top and pull back as my foot comes down off the bottom, but there's 
little to no gain from pulling up.  Without toe clips, it's hard to keep your 
feet on the pedals while spinning faster than 90 or so.  With toe clips, you 
can spin over 100 and stay with the pedals.  Depending upon your size, 
aerobic health and style, you should spin consistently at over 70 and cruise 
on level ground somewhere between 80 and 95 for your entire ride. You won't 
be a sack of hammers.  You'll like 'em!
VF> Also - is there much difference between the kinds of pedals
VF> and clips?
I can't be of any help here.  I use, and have used for years, the Shimano 
Look style cleats.  They work fine and they seem to be cheaper than many of 
the alternative types.  That's all they had when I started though.  Seems 
like there's three or five different ones out there now.  Perhaps someone 
with a varied pedal experience can help.
                                  Dewey

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