Nitric

I Believe In The Fact That Doctor Strange Is Immortal, Immortal In My Mind Meaning He Can't Die From Natural Causes (I.E. Disease, Old Age, etc..) But If Someone Stabs Him In The Head, Yeah, I Think He'd Die.

Yeah, I Hate That Too. Dr. Strange Is One Of My Favorite Characters, And Easily One Of The Most Powerful, But He's Mainly A Plot Device It Seems. I Think He's Been Stated (Don't Quote Me On This, And Sorry If I Sound Stupid) But A 'Deus ex Machina' Which Is:

  "The phrase has been extended to refer to any resolution to a story that does not pay due regard to the story's internal logic and is so unlikely that it challenges suspension of disbelief, allowing the author to conclude the story with an unlikely, though more palatable, ending."

Meaning Kinda, That, Dr. Strange's Power Is Dependant On What The Writer Needs As A Scapegoat. =)

I Hope That Helps You A Little Bit, If Not, Im Sorry!