A guide is just a guide. You don't need to follow it blindly, you can still use your own simulator before sending troops. Sometimes I find a better solution and when i don't forget I post it here Some of the better solutions are just created by an different playing style.
One of the different playing style solution is for instance the first attack at the tower in The Witch of the Swamp. Mimori guide is stating to send 200r. I always choose the option of 15R,132Bowmen.. More expenisve in brew and less expensive in settlers. My solution takes longer to recruit, the guide solution is easier as you are getting way more swords then bows in the same time.