It's most assuredly a concern; I discovered the problem back in the mid- to late-80s when I built my ITA Rabbit GTi. But, it's a "problem" that cannot be cured legally.

OK, so you have an axle binding problem when you lower the car below a certain level. The legal solution? Simple: don't lower your car that much! My current suspension's roll center drops like a rock under ground level when I lower it too much (starting WELL above the allowed 5 inches) and the car's handling goes funky; can I relocate the pickup points to compensate? Of course not! You have to work withing the design of your car and within the IT rules to find the best compromise.

To do anything else is CHEATING.

If you shorten your axles YOU ARE A CHEATER.

Capiche?