Great thread this. As I'm sure many here are fed up of hearing I financed my uni degree by emptying ace machines, but I was nowhere near as expert at it as some others. I simply only took line wins which kept being available on the exchanges even after it forced jackpot wins on me.
I'm not technical at all, but to me it would seem to be a simple one extra line of code to make sure the machine counted any band aid wins as well as reel wins, and tightened up once it started getting over the RTP.
But given the guy who wrote these programs went to jail for leaving this exploit, maybe he buried it a bit to make it harder to fix once discovered.