That's the hard way Bear.
Louis, all you need to do is use an ablating antifoul. Altex, ABC 3 etc. That is one that wears away like soap. There is a constant active surface as you use the boat or scrub it as necessary.
As soon as the boat comes up out of the water just gernie it off. If there are barnacles just get a heavy paint scraper and chop them off. THe gurnie gets rid of all the paint so you're backto the original surface. Wait for it to dry and mask off with 50mm wide masking tape around the waterline. and go for it.
If you have extra paint, use it up on the areas where you get turbulence, ie the wind n water line, leading and trailing edges or edges where you get a sharp edge. There is no build up, messy sanding and you're not getting covered in toxic paint.
I always put two generous coats on. The old antifoul sometimes peels off, just flick it out of the roller and keep going. This is a recommendation from someone who actually slips their boat yearly.
Don't let it go too long. Once you get barnacles you can get gelcoat damage. But that won't worry a Top Hat.
Ask around locally to see what works best as different areas of the same bay have different antifouls that work. You may even find that the antifoul works on one side of your boat and not on the other.
Look along the hull for blisters while the hull is wet and don't be worried if you get some.
It is one of the easiest jobs to do in boating. If you stuff it up only the one that got away will see your mistakes.
What Rob is doing is good protection for the future.