I guess I read NM’s description as if the car rolled over and Tony, with barley a blink, turned to Christopher and killed him. I was just saying that there was much more then ‘barley a blink’ going on there. Yeah, it was opportunistic, but it’s not like Tony thought of this as they were rolling down the hill.
The thing I notice when I re-watch the show is how they had to divvy up the prime elements that they were setting up to be Livia’s character arc between Uncle Jun and Janice. Uncle Jun got the senility and the trial and Janice got the borderline personality disorder and the nagging.
If Christopher hadn’t been high, Tony probably would have made the 911 call. I believe he expected Tony to lie about who had been driving, and that’s when Tony becomes disgusted and closes the phone.
Tony always had a soft spot in his heart for helpless animals and babies. Remember how he responded when he found out his racehorse, pie o my - was killed? I think the turning point with Christopher was seeing the babyseat in the back of his car with the tree impaled through it. It was immediately after seeing that that he closed the phone and killed him.
I think we are on the same page here. It was rational, calculated and cold rather than an impulsive violent act. That’s what made it so chilling.
The “barely a blink” was referring more to the execution of the act rather than the decision.
edited to add: I just realised I used the term “execution” isn’t the subconscious a wonderful thing? (and that in itself is Dr. Melfi to a “t”) (and to a “t” is rather apt as well…have I finished now?..yup, that seems to the be the last tenuous reference)
I think it was more that Christopher revealed that he was back on drugs, and hence was a major liability. Tony couldn’t afford to have one of his confederates that was that unreliable and subject to pressure from the FBI, especially when he was facing indictment.
Essentially that’s it. Tony warned Christopher two years earlier that he only had one chance to stay off the drugs. When Chris implied to Tony that he was high, that was the last straw.
This discussion about Christopher vividly illustrates the depth of The Sopranos and the involvement of the audience. Its one scene in 80 hours yet people will re-examine it and argue the most subtle details.
I used to belong to a Sopranos forum (now gone) and threads running for pages would focus on specific scenes with passionate arguments expanding in all directions. Very few television shows have that.
Whaaa you mean to tell me, years after it’s off the air, we won’t be discussing the subtleties of How I Met Your Mother or Reno911…You sir, need to get your head checked.
Well…ah always did hanker to chew the fat over the Red Green Show. You up for that cousin? 
Cousin? I’ve been calling you pa all these years.
Boys, boys. You can be both!