I'm a well read grad student who's bluntly honest about all things, although I try to be most honest about myself.
His compassion is what drives him, and it's something not all authors get. Duggan and Aaron have been nailing it so far, though, to the point where I don't want to read Doctor Strange stories if they haven't been written by them.
Sometimes it's small things, but with Deadpool, it's always been pretty huge sweeping statements. Before, yes, he was helping Deadpool, but I loved him for one of the smaller things: just pointing out that Deadpool was human and deserved a little dignity. It was something that Wolverine and Captain America probably thought was so obvious it didn't need to be said, but you know what? It did. Wade needed that. I needed it as a reader. Wolverine and Captain America completely dismissed Wade, and I was so tense by the time Strange said this, that I could feel my shoulders drop and I was on the verge of tears, thinking, 'yes, finally.'
It was the easiest thing anyone could have done. It cost them nothing except a couple seconds of time, and yet it meant so much to me that the moment stuck out in my mind. I latched onto it, and fell in character-love with Strange for his kindness and empathy right then and there.
So, yes, Doctor Strange shows up in this issue, and this happens:

See, Strange played with Deadpool's memories, making him forget he killed his parents. It's not quite in character for him until this card is played:

That is in character for Strange. And having heard this story now, I doubt many other Marvel characters would cheerfully say that Deadpool was making progress. Or let him back in their house. See, Strange could refuse to see Deadpool. He could run, he could put up better magical protection, but, no, Deadpool is welcome into his house. At whim, it seems.
It doesn't show how he got into the house, but I like to think that while Wong got the gun to shoot Deadpool - if necessary - Strange welcomed Deadpool himself. (Usually, I believe it's Wong who welcomes people, although that just might be when Strange is out, or busy astral projecting.)
Deadpool has issues with people tampering with his memories, though, so I can see why he'd have this love/hate issue with what Strange did. Yes, it was for his own protection, but then his memories are ever shifting, so he might just have forgotten that he asked for this and Strange gets a pass.
Just as I was thinking all this, another panel explained it all.

Not only does he keep forgetting, both he and Strange came up with a way to keep him from killing Strange. I have a feeling that this was after the first time he tried to kill Strange, because I don't think Strange would think of this, and neither would Deadpool. But it's not explained.

I don't think Strange is excusing Deadpool, not even to Wong. He's just saying it's tragic that he's a maniac. He was made. The things that were done to him were inhumane. And despite Deadpool turning into a maniac, despite the things he's done and has continued to do up until this point, Strange can still feel badly for him. Because not only does he see the evil that was done to him, I think Strange sees him as a good person protecting himself in any way he can after all this horror.
Or I like to think so, and nothing in canon has proven me wrong yet on this point.
Anyway, Deadpool, Sabertooth, and Doctor Strange? What did I do to deserve all this goodness in one issue? I need to know so I can get more goodies like this.