People can follow the process. Many people (most?) won't follow the process.

In the U.S., at least, it has been observed that roughly 10% of drivers adhere strictly to the limit. The rest drive the speed they find comfortable.

<England> Clearly the solution is to add Orwellian levels of automated ticketing</England>

Sarcasm or wishful thinking?

Both are valid points one could argue for, depending on underlying values that are not necessarily rational.