Road racers occupy the entire performance envelope of their machines and spend a great amount of time in extreme bank angles dragging knees and elbows. A car tire in that scenario would be totally unsatisfactory since it is not capable of supporting traction/adhesion at those angles. Conversely, most of us never get anywhere near the performance limits of our machines and while touring, highway cruising and riding "honey-do's" to the grocer and pharmacy spend most of our sedate riding nearly straight up, cornering at reasonable bank angles (klaviator excepted!) leaving generous "chicken strips" on our oval cycle tires. Clearly, even to the less educated, we have two entirely different performance applications. The only mutual connection is the two wheels on each end of a motorized frame. The racer needs the tire to last the race. The recreation rider needs the tire to outlast the season. And stay within the budget. Now over the years I have learned from many people, some with great, long experience and some nuggets with a fresh outlook. I have learned to listen to a great many people and have learned to ignore many, mostly the ones with closed minds. The most recently ignored was a PhD who was totally off base and totally commited to his ego. He was asked a question he was ignorant of the answer. He was actually ignorant of the fact he was unaware the very thing he believed strongly did not exist in the very book he used as a reference. His ego got in the way of knowledge and truth. He put too much faith in "we always have done it that way" and "that is the policy."