Fix some cases where macros were not used consistently.

Signed-off-by: Daira Hopwood <daira@jacaranda.org>

protocol/protocol.tex

@@ -639,7 +639,7 @@ The encoding of a \coinPlaintext consists of, in order:
 \end{center}
 
 The \coinCommitmentTree is an \incrementalMerkleTree of depth $\MerkleDepth$ used to
-store \coinCommitments that \PourTransfers produce. Just as the \term{unspent
+store \coinCommitments that \pourTransfers produce. Just as the \term{unspent
 transaction output set} (UTXO) used in Bitcoin, it is used to express the existence
 of value and the capability to spend it. However, unlike the UTXO, it is \emph{not}
 the job of this tree to protect against double-spending, as it is append-only.
@@ -797,7 +797,7 @@ $\pourDescription$. \\ \hline
 
 The $\ephemeralKey$ and $\encCiphertexts$ fields together form the \coinsCiphertext.
 
-\todo{Describe case where there are fewer than $\NOld$ real input coins.}
+\todo{Describe case where there are fewer than $\NOld$ real input \coins.}
 
 \subsection{Computation of \hSigText} \label{hsig}
 
@@ -1098,9 +1098,9 @@ the \authKeypair private key $\AuthPrivate$; the coin is unspent if and only if
 $\sn = \PRFsn{\AuthPrivate}(\CoinAddressRand)$ is not in the \spentSerials
 for that \blockchainview.
 
-Note that a coin may change from being unspent to spent on a given \blockchainview,
+Note that a \coin may change from being unspent to spent on a given \blockchainview,
 as transactions are added to that view. Also, blockchain reorganisations may cause
-the transaction in which a coin was output to no longer be on the consensus
+the transaction in which a \coin was output to no longer be on the consensus
 blockchain.