For example, in the Volsung Saga Sinfijolti is a hanger on Heroic Spirit to Sigurd, it's fine since he gets a lot of screen time and has his own chapters of the legend. Then however you have another Heroic Spirit one step further removed, a hero named Helgi who accompanies Sinfijotli and performs some great deeds before disappearing. 

Helgi would also be a Heroic Spirit, but his stats would probably look something like Strength: C Agility: D Endurance: C
For a Noble Phantasm he has a fairly regular Phantasmal Horse or something. 

Helgi would get his ass killed by Lancelot, probably within a few rounds of combat. He would get his ass killed by Astolfo to, because unlike Astolfo he does not make up for his low stats with a kickass Noble Phantasm. There are a lot of Helgi's in difrent legends through history, and it's these Heroic Spirits that someone like Cuchulain is being compared to when it says that he's a truly exceptional Hero.