One last question....
To make a rule like this you can set the condition to 'Subtotal for any column' then select the TotalWeight column and select is <= a value of 1.
Then for the calculation you would choose 'based on column subtotal' and choose the total weight column and 'times' then the factor you would like to multiply it by.
Once you do this you will want to update your UPS rule so that it has an additional trigger in the condition. In here you will set it to 'Subtotal for any column' then select the TotalWeight column and select is > a value of 1. This will ensure that the UPS rule will only trigger if the total weight of the cart is more than 1. With the rules setup like this it should use only one or the other, but not both.
Thanks for all your help, everything is working great.
One last question. I just realized that if I have items in the cart that are less than one pound and then I select "clear cart" the shipping weight remains the same when I add new items to the cart. This is the same problem I had above with the UPS shipping until you showed me how to add the code to clear the UPS session variable. Can you also show me how to clear the variable for the rule we just created for items that weigh less than 1 pound?