Add: Proving general computation section

bip-PC.md

@@ -119,26 +119,6 @@ ELSE
   <settlement-n-hash> CTV
 ENDIF
 ```
-
-### Use for proving computation
-
-Merkle trees can be used to prove out computation where the root of the tree
-represents the function and the leaves represent the inputs and output. There
-are practical limits to the entropy space for the inputs as it needs to be
-iterated over and hashed up.
-
-Currently MAST trees can cover 128 bits of entropy space, which is well over
-the practical limits to iterate over and merklize. Therefore we assume this
-capability does not materially extend what computations are possible to prove
-out in bitcoin script. While `OP_PAIRCOMMIT` is not limited to a height of 128,
-that should not be practically feasible to utilize.
-
-There is a way to reduce the size of the witness for proving out computation,
-by eliminating the merkle path inclusion proofs, using `OP_CHECKSIGFROMSTACK`
-together with `OP_PAIRCOMMIT`. This method involves deleted key assumptions,
-most likely using MPC to create an enormous amount of signatures for the stack
-elements representing the inputs and the output of the function.
-
 ## Reference Implementation
 
 A reference implementation is provided here:
@@ -180,6 +160,25 @@ various reasons, either for expanding the scope or for unnecessary complexity:
 * OP_CHECKSIGFROMSTACK on n elements as message
 * OP_VECTORCOMMIT: generalized form for n > 2 elements
 
+### Proving general computation
+
+Merkle trees can be used to prove out computation where the root of the tree
+represents the *function* and the leaves represent the *inputs* and *output*.
+There are practical limits to the entropy space for the *inputs* as it needs
+to be iterated over and hashed up.
+
+Currently MAST trees can cover 128 bits of entropy space, which is well over
+the practical limits to iterate over and merklize. Therefore we assume this
+capability does not materially extend what computations are possible to prove
+out in bitcoin script. While `OP_PAIRCOMMIT` is not limited to a height of 128,
+that should not be practically feasible to utilize.
+
+There is a way to reduce the size of the witness for proving out computation,
+by eliminating the merkle path inclusion proofs, using `OP_CHECKSIGFROMSTACK`
+together with `OP_PAIRCOMMIT`. This method involves deleted key assumptions,
+most likely using MPC to create an enormous amount of signatures for the stack
+elements representing the *inputs* and the *output* of the *function*.
+
 ## Backward Compatibility
 
 By constraining the behavior of OP_SUCCESS opcodes, deployment of the BIP