Why not sudden strike?

[Tsillanabor]

I'm playing a ninja/duellist and would love to apply Telling Blow to my Sudden Strike ability, but it says skirmish or sneak attack. So, why not sudden strike? Or is sudden strike included under sneak attack as implied in the sidebar in Complete Adventurer?

 

[Notmousse]

Sudden Strike is for all purposes treated as Sneak Attack except for when it would apply.