translation =
..but I guess they were warning these are pretty hard core settings.
Softer front springs help traction (and braking too - actually quite a lot!).
Stiffer front springs will help stability, but will cause understeer and cause tyres to heat up more although heat is not really an issue for road use with good tyres.
True for pure road use you may wish to play safe and not wish to cause the tail to be frisky.