I havent been able to find a flaw in regards to line management
You can read a little bit more (and hear the short audio interview) about this fascinating fish study with Chris Pullen here
This includes everything from the earliest Pflueger casting reels like the Kentucky and Quadruples, to the popular Redifor, Norka, Buckeye, Worth, Trump, Trusty, Nobby, and Skilcast, to the obscure Free Speed, Prokast, and Fas-Kast reels, just to name a few
This change can make the difference in these situations
Its subtleness is one of its greatest strengths, but it also requires greater concentration and feel from anglers in order to differentiate bottom contact from an actual bite.