Smoothing out speed spots that are already pretty good.

Surely the best use of resources would be to "mow" a Channel through a thick area of weed. This would make easier to be at the correct angle and depth plus you could mow multiple channels side by side for a drag racing style event

No need to mow a channel. Better to just run in the weed.

The issue at L. Illawarra, as I understand it, is that there is less weed than there used to be. The water is no longer pure glass.

There are a few places where a little bit of wave and chop grooming could make a big difference. Eg boob bay shark bay, awesome when the tide is right but you have to cross a choppy channel which slows down the entry speed and it gradually curves and the coarse gets deeper and deeper. If you could smooth that entry chop and smooth the chop when the tide isnt just right you could go from a few hours of magic to a lot of hours of magic and make a longer perfect course. Same thing on swan river, there isnt any weed and its almost good but not quite and to get wind strength direction tide and lack of boats to match up is rare. Of coarse we are lucky to have other spots nearby but not always time to drive to them. a few ideas i have had are second hand wood power poles, or poly pipe or lay flat hose inflated, sheets of form ply laid flat as floating rafts, a fence banged into the sand from colorbond and msybe starpickets, lane ropes, a massive tangle of second hand craypot rope like a weed bank, second hand carpet. I have also thought about building a hundred six meter long boats to tie in a line. Or poly road barriers. All pretty big to transport and time consuming to set up. An excavator could build a small breakwater. But then you would never get approval.
A promising way could be foils optimised for speed. Less wind needed due to less drag and less problem with chop. I think that is a good path for development but will need lots of improvement from current foils optimised for low speed takeoff and normal winds.

Coodanup foreshore, before the 'Cut' at Dawesville was completed in 1994, was a toxic expanse of algal blooms over summer. The Waterways Commission had a bigger version of the harvester above, moored in the Serpentine River. It was used extensively over the summer months. The ramps along the Coodanup/Nairns foreshore where used by front end loaders and trucks to gather up the algae/weed on low tide and the harvester would be working on the higher tides. The sand was black, slimy and stunk to high hell. Sigh...., the good ol' days when mowing weed was hardcore. ( I still think a body drag from Jonski is the best method to clear a speed run)