I think this issue is WAY over-blown… Putting new tires on the front is certainly going to change the way the car steers. Most drivers quickly figure this out and compensate their steering responses and stay out of trouble…When you put them on the back, the steering response stays pretty much the same as it was so accident investigators and trial lawyers are kept under control…
Conventional wisdom say the new tires will have better grip under all conditions but that’s simply not true. The worn tires are likely to have better grip on dry pavement, where most of us spend 90% of our time…So the cars handling characteristics will always be changing depending on road conditions. All of this could be sorted out on a skid=pad, but few of us leave the tire store and head for a skid-pad…