I completely disagree.
1 was a given, since Walt had seen the room before and thus knew exactly how to park the car.
2 was irrelevant, he wanted to get Jack, the rest were a bonus. He wasn't expecting to survive the attack. He only got down in order to protect Jesse, who wasn't supposed to be in the room.
3 Jack would never have had his goons shoot Walt on sight. That's just not how he operates. He didn't fear Walt at all, saw him as a dying old man.
4 The goading occurred, because they took his keys away. That clearly wasn't part of the plan, but it was easy enough to pull off. Pride is a dangerous thing.
5 No one had ever searched a car before throughout the show, I'm willing to bet no one in such a situation would. Even if it had a bomb, they were safe inside the house. The most critical part of the plan was getting the car parked correctly, but that's an easy enough con. Who's gonna argue with the old guy with cancer that you're gonna kill in a few minutes anyway? What would be the point?
I'd say in real life, against real life thugs the plan had a pretty good chance of working out IMO.