Distressed and fatigued equal or more than stat?

By Silverwave, in WFRP Rules Questions

p.62 under The Effect of Fatigue and Stress, it's stated that "When a character has suffered stress greater than one of his mental characterictics..."

So, logically, if you read it as it is, if you have a Willpower of 4, for example, you must aquire 5 stress.

But then, in the example on p.63, Suriel has a Fel score of 4 and accumulated 4 stress, it's stated that is Fellowship is distressed.

So is it EQUAL or GREATER stress than the characteristic, or really GREATER ?

Greater than the characteristics.