Howling:When the Doctor died in Turn Left...

did he really die too quickly too quickly to regenerate? Or did he simply refuse to regenerate?

As we all know, Turn Left focused on an alternate history where the Doctor died during the events of "The Runaway Bride". So, I was watching the episode again and when the Doctor's body is put into the ambulance, the UNIT soldier suggests that the Doctor did not regenerate into his eleventh incarnation because "it happened too fast" but there has been another theory: that the Doctor chose not to regenerate.

According to this theory, the Doctor let himself drown because of his depression over losing Rose. This idea has been portrayed in several fanfics on Turn Left such as this: http://www.fanfiction.net/s/4543093/1/Drowning-Pains. Some would say that the Doctor would NOT just let himself die because he lost her. They argue that he lost several friends and STILL continued on, he said goodbye to several companions when they left him and he STILL helped the Earth.

But there are several reasons to believe in the theory that the Doctor chose not to regenerate as opposed to the "it happened too fast" claim.

1. In "Last of the Time Lords", it is implied that regeneration is an option which can be chosen, since the Master refused to regenerate after being shot by Lucy Saxon, despite the Doctor's pleas.

2. You gotta admit, the Doctor did seem almost suicidal after losing Rose since he did demand the Daleks to kill him in Evolution of the Daleks (even if he was faking it)

3. When the Doctor just watched as the Racnoss drowned, his eyes were full of darkness and pain.

I know this almost certainly did not happened in the episode but I love the theory that the Doctor chose not to regenerate and that he thought of Rose as he died.

So what do you think? Did the Doctor refuse to regenerate when he died in Turn Left?