Frighten and Terror confuse instead of scaring

[Saxon]

I have a quick question on Fear.

I looked at Frighten in the manual, which says one square gets hit with a Fear +15 attack. Terror on the other hand, hits multiple squares, but is said to have a Fear +10 attack.

However, the manual also says that there is no modified to a Fear attack, the + value just indicates the number of squares effected. As such, I am confused. Do these values mean anything?

Also, the manual indicates that a squad can only check morale once a round. Once they are damaged enough (or the army is) they check every round. Based on that, once an enemy army is beat up fairly badly, the fear spells and effects are a bit pointless.

Can any one clear this up for me?