Hope my post didn't come across as advocating dependency on a bow thruster. They can be a nice asset, but the skipper who stakes the outcome of every maneuver on an effective thruster is already in trouble.
The larger point has to do with the "prudent mariner" mindset. Aviators know about this, where a pilot is trained to be ever-mindful of what to do if something stops working as it should. The mind of a pilot (at least, any pilot I want to fly with) is always out in front of the aircraft, anticipating things. Not living in terror of failure, but with a bag of options in mind, just in case. As the old saying goes, "there are old pilots and there are bold pilots, but there aren't many old bold pilots." Chuck Yeager, who lived to 97, used to be the exception that proved the rule.
When zooming into a parallel space along a face dock, I would approach just as Mobcat says, at a 45-degree angle (or greater) with plenty of way on. Shifting into reverse, I would wait to feel the tranny engage, then as the bow entered the perimeter of my docking space, begin goosing the throttle. As way came off, the rudder became ineffective, but prop walk took over. With judicious surges of RPMs, the propellor simultaneously killed the boat's forward momentum, and swung the stern in against the face dock, while the bow swung away. Sideways momentum laid the boat's entire length against the dock, where it remained motionless, like an obedient Black Lab. When everything happened perfectly, I could step away from the helm, pick my my breast line, and step off onto the dock to make it secure just as the rub-rail gently kissed the pilings.
What could go wrong? Well, let's see: a shifter or throttle cable could break, the aforementioned tranny failure could happen, the shaft could decide it was tired of spinning repeatedly in opposite directions under heavy torque and shear apart, or the wheel could spin off the end of the shaft. None of those risks are likely. But if any one of them happened, the rudder would not have saved me. I would have been guaranteed to crash into either the dock itself or another boat. Besides the property damage, the harm to my personal dignity would have been unthinkable!
The more time I spent on the water sharing sea stories with other boaters, the more I realized that every point of failure mentioned above not only could happen, but had happened, to someone else. Why couldn't they happen to me?
By the way, that was before electronic shifters and controls became commonplace. Just about every boater I know who has used electronic controls has experienced some kind of glitch - including me.
Accidents result from more than one point of failure. We all do what we can to prevent those failures from happening, but they will. If failures ever start to gang up on me, the easiest thing I can do is eliminate from the list of contributing factors the one that says, "the captain was being reckless." Not suggesting that anyone else is reckless, here - just sharing what has made me more cautious or at least risk-averse over the years.
On top of everything else, there is also now another new threat to the skipper's dignity: the YouTube videos called "Boneheaded Boaters of the Week." Don't ever want any of my dockings to appear there!