I totally agree about chassis flex and chasing your tail with too stiff suspension, Jimmy.
A front anti-sway bar INCREASES understeer, which is important on Speedsters.
A factory 12mm bar helps keep the front end flatter. IMHO the 3/4" bar is too much stiffness in a lighter-than-stock Beetle chassis.
In the early 70s, there was a 5/8" aftermarket bar available which was a nice compromise for street handling. That's why I built a 5/8" custom bar for my Spyder. It works great. Too bad they aren't available any more.