I understand all the docking concern, but that's such a small part of what one needs to learn. What happens when you go out in 3-4' and soon it turns to 6-8' and you have to cross a bar or inlet back in? Are you prepared? Are you prepared to handle rough seas from any of the four directions? And learning not just to read your instruments but to read the water? Even soft groundings ruin many boaters days. Also, checks you should run every time before going out and those you should do while underway. Are you both prepared to replace the Racors while at sea? If you have twins, what happens if you lose one? Can you handle it still? Even basics such as when to call the tow company for help rather than waiting too long and when to call the CG and call Mayday. What about MOB?
Now there is a balance to avoid scaring newcomers. However, we found knowledge and confidence to greatly reduce an anxieties we might have otherwise had.
As to docking, we practiced for hours over many days while at sea with invisible docks, but learning how the boat handled at slow speed with wind and waves from all directions. Then at quiet docks. There you can learn simple things too like the difference in how your boat backs to port vs. starboard.
If you have a couple of professional trainers for three days or even more, you can mix these tougher parts in with the pleasure and easier and basics. You can enjoy each of you docking at a restaurant for lunch and just cruising up the ICW and back on the outside.
We also had challenges of working with instruments only, mimicking conditions with no visibility. While the trainers could see, all we had were our instruments. You're forced to get comfortable with radar. Then the reverse, working with no instruments.
Now, one caveat, before this I would suggest a basic course of some sort so that you know the language, know the markers, the basic rules of navigation and even know docking in theory. That way the on the water training proceeds far more quickly as you've got some knowledge.
Plus, if it's your boat you'll be learning on, you should know the instruments all very well in advance. Read the manuals, play with all the settings. All of this is to allow the training captain to be as efficient as possible. Talk to them about what they'd like you to learn beforehand.