I do think using a knife on a snake should be the absolute last resort, but I also don't see a reason to ridicule someone for being safe rather than possibly dead. It's not like anyone here is saying that if a big snake bites you and starts to constrict, you instantly cut its head off. A knife is a safety precaution that some people choose to use when all other options have been exhausted.
dde1878, I do completely agree with you that there are a LOT of people that are NOT suited to keep big snakes. People that just want it for the shock value or because it's "cool" have no place having (purposely didn't use the word "keeping") these animals. Also people who go in with an extremely defensive mindset, ready to cut down the snake at its first false move have no business having these animals, as you've mentioned. You on the other hand are definitely a "keeper" and not a "haver" of these animals and I really respect your opinion and experience in this matter. You really seem to know what you're doing and are really a master over your snakes. (and just to be clear, that was completely serious, no sarcasm intended-although some may follow

)I find it quite childish however calling someone a "tard" or "Crocodile Dundee" because they believe in a last ditch safety measure that you don't. I have never personally kept large constrictors and don't have any immediate or future plans to (I really would like a carpet python some day though...), though I have worked with some a little bit. However, if I did, I'd rather have a some last safety measure that was NEVER used on a snake because that one in 10 trillion situation in which it was needed NEVER came up that have it come up and be unprepared if it were to happen just cause some guy called me a "tard" on the internet.
I see no one here advocating the slashing of evil, extremely dangerous snakes if they so much as look at you, because they aren't evil or particularly dangerous when handled correctly. I understand you feel strongly about this, but a little civility never hurt anyone (and generally gains some respect-at least in my eyes-as opposed to losing it by calling people "tards" lol)
Would I carry a knife if I had a big snake? Probably not, but I don't think it's wrong for an intelligent person to do so either, especially if it is simply for a little psychological comfort. Someone going in expecting a fight/attack with the knife at the ready...they are the ones who shouldn't have the snake (or knife for that matter lol)