Oh Captain My Captain:

First of all, I consider criticizing Steve Yzerman as a crime in my book. A crime comparable to shooting your mother point-blank in the face with a shotgun. Everyone who watched the 2002 Stanley Cup playoffs winced with Yzerman every time he tried to get up from being knocked down. Everyone realizes that the amount of pain that he put up with would have put a normal player on injured reserve for weeks. He almost single-handedly brought the team back from a 2-0 series deficit against Vancouver. The man has the constitution of a horse and is revered in legend, folklore, and the minds & hearts of eternally grateful Wings fans.
Sergei left because he did not want to live in Yzermans shadow anymore. He saw how Yzerman was loved by the fans, and he wanted part of it. He felt jealous, felt like his talents were wasted on a city that worshipped his captains every footstep. He played his best games when Yzerman was injured because without the captain, the spotlight was all his. When Yzerman returned, Sergei felt dismissed as just another player.
Keep in mind that Yzerman has steered the Wings through rocky waters in the late 80s thru the mid 90s. He was almost traded by the revered Scotty Bowman in 1996. Cooler heads prevailed preventing that disaster from ever happening. Yzermans quote on his possible trade was the following:
Ive had a good career here, and would like to remain here. If the management thinks things would be better if I go then I accept their decision.
There are two kinds of players: Ones that are in hockey for themselves, and ones that are in it for their team. Yzerman has always been in it for his team. Plus, youre talking about a man who willingly accepted the task of scoring less goals in order to improve his team defensively. Would you get that same response from Fedorov? I think not.
It seems fitting that Yzermans 2002 saga can be described by Walt Whitmans Oh Captain! My Captain! poem:

O Captain! my Captain! our fearful trip is done,
The ship (Red Wings) has weather'd every rack, the prize (2002 Stanley Cup) we sought is won,
The port (Detroits Hart Plaza, site of the 2002 victory parade) is near, the bells I hear, the people all exulting, While follow eyes the steady keel, the vessel grim and daring; But O heart! heart! heart!
O the bleeding drops of red,
Where on the deck my Captain lies,
Fallen cold and dead.

O Captain! my Captain! rise up and hear the bells;
Rise up--for you the flag is flung--for you the bugle trills,
For you bouquets and ribbon'd wreaths--for you the shores a-crowding,
For you they call, the swaying mass, their eager faces turning;
Here Captain! dear father!
This arm beneath your head!
It is some dream that on the deck,
You've fallen cold and dead.

My Captain does not answer, his lips are pale and still,
My father does not feel my arm, he has no pulse nor will,
The ship is anchor'd safe and sound, its voyage closed and done,
From fearful trip the victor ship comes in with object (Stanley Cup) won;
Exult O shores, and ring O bells!
But I with mournful tread,
Walk the deck my Captain lies,
Fallen cold and dead.

-Walt Whitman (1819-1892)

For seven months, Yzerman died as doctors repaired his knee. Now the honored god lives once more. How effective can he be? 

Yzermans role in the locker room affects the team much more than on the ice. He wont score as many goals, or grab as many assists. His presence brings the kind of animal magnetism that makes players feel at ease when hes on the ice. Deep down in their minds, they all know that when Stevies out there things are going to be ok.