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Paolo, I did read your answer. I wonder if you understood mine? If not, I'm sure the fault must be mine as I must have been unclear.
Although this is a frame-relay instance, I generalize that shaping to the physical link capacity is "pointless". This directly answers the original poster's questions about usage of the shaper in the configuration snippet shown.
I further generalize that when you're working with WAN cloud technology that supports sites with different bandwidth capacities you may want to shape to the far side's capacity, if it's less.
Do you disagree?
As to your answer, you correctly note why shaping to frame-relay's CIR might be done. Another good generalization, however, since the original posting's config implies we're shaping at link capacity, implied by both the serial interface and single subinterface configured with the same bandwidth, although we don't really know if that's truly the case (i.e. fractional T1/E1 or not), but if true, removing the shaper would still permit rest of the policy to function normally at link congestion. Here, I believe, my "pointless" answer might better answer the original poster's questions, then assuming it's set to CIR. I do agree shaping to CIR is one common usage of a shaper for frame-relay, didn't mention it my post since yours did, but also consider having CIR set to link capacity is unusual. In such cases though, my "pointless" answer would still be true, but with your answer this distinction isn't clear.
Oh, and just to further clarify, I also agree that you don't usually need to shape to CIR (or ATM's SCR or MPLS "flavor" of CIR, e.g. CDR), in most cases, with the exceptions you noted, which I've encountered in some countries.
