Games Magazine - Letter-Swapping

Letter-Swapping is a Games Magazine puzzle that is kinda complicated. You have two columns of Words, and the a letter swaps from each side. In fact, I still don't really understand it, I'm going to present the instructions verbatim from the magazine:

Some words are so compatible that they can exchange letters, like pen pals. For example, LETTER and SWAPPING can trade the L and W to make WETTER and SLAPPING. In the puzzles below, you'll make such swaps between the soul mates in opposite columns. In puzzle A, for example, you can switch the C in RECENT with the P in RAPIER to create REPENT and RACIER. But beware - some switches have hitches and may land you in the dead letter office! Once you've made an exchange, put the switched letters in teh spaces provided. In the example, C is placed in the space next to RECENT and P in the space beside RAPIER. If you've made all the right swaps, the two groups of letters will spell out two more soul mates that can exchange letters. Making that switch leads to each muzzle's final answer. So swap 'til you drop!

#!/bin/bash
for EACHWORD in `cat col1` 
do
#EACHWORD=recent
	LETTERCOUNTER=0
	WORDLENGTH=`echo -n $EACHWORD | wc -c`
	for EACHLETTER in `echo -n $EACHWORD | sed 's/./&\n/g'`
	do
		for NEWLETTER in `cat thealphabet`
		do	
			#replace that letter with a differeint one
			NEWWORD="${EACHWORD:0:$LETTERCOUNTER}$NEWLETTER${EACHWORD:$LETTERCOUNTER+1:$WORDLENGTH}"
			OLDLETTER="${EACHWORD:$LETTERCOUNTER:1}"
			if [ "$NEWWORD" != "$EACHWORD" ]; then   #WE cannot have the same word again
				grep -x $NEWWORD /usr/share/dict/words > /dev/null
				if [ $? -eq 0 ]; then #Our new word is legit
					
				echo A new word is $NEWWORD
							


					

				for CANDIDATE in `grep $NEWLETTER col2`
				do
				NEWWORD2=`echo $CANDIDATE | sed "s/$NEWLETTER/$OLDLETTER/" `
				grep -x $NEWWORD2 /usr/share/dict/words > /dev/null
                                if [ $? -eq 0 ]; then #Our new word is legit
				#echo "Our new word is $NEWWORD (exchanged $OLDLETTER for $NEWLETTER on space $LETTERCOUNTER)  "
				echo -n "$OLDLETTER $EACHWORD ($NEWWORD)"
				echo -e  "\t $NEWLETTER $CANDIDATE ($NEWWORD2)"
				fi
				
				done
										





				fi
			fi 
		done
	let LETTERCOUNTER=$LETTERCOUNTER+1
	done
		


done