This idea is based on a problem that I see in real life, that a group of citizens who are... Oopsie... who I perceive as frustrated/utopian/uninformed want to try a really brilliant idea, and as it is a democracy if there is finally majority supporting it, then they are right.
In the most clear cut scenario the idea actually involves a combination of spending and taxation ideas that terribly mismatch, and not only I am prejudiced against such idea but it seems that basic mathematics says that the numbers do not add up. Sometimes the idea is more subtle, like basing the brilliant plan on some perceived harm from outsiders and hoping that closing the border for trade or for foreign investment would solve the problem. Or introducing some law because of some high ethical ground or patriotism, that after closer inspection looks like poorly veiled vested interests of some minor group.
The aim is:
1) To let some bad idea actually being tested on some area, instead of trying to introduce it on country level at start. Instead of heroic fights who would get the majority even an idea supported by minority would get some chances. As result after voters seeing the result, the politicians would not only no longer support it, but actually claim that they were against it from start.
2) To ask populist politicians to test their brilliant plan in such province (even if by all metric the plan even more or less work, they would have to prove themselves as administrators who have to make hard choices and not only as great speakers)
3) Actually from time to time a scorned idea may turn out to work quite well. So it would be just seen as working and introduced at central level
4) Under perfect scenario - if the regulation worked quite well, then actually local people would benefit from it sooner than the rest.
Would it be possible to implement such policy?
When thinking about it I found a few problems:
1) What if policy works locally but the cost are being transferred to the rest of country. Ex. Running a tax heaven. Or selling locally lots of unmonitored weapons, or drugs that sip to other provinces. Or polluting whole region.
2) What if such experiment works a bit better and effectively is a big version of walled community? Which works indeed a bit better than the rest of the country thanks to keeping some undesirables out.
3) Would it actually convince many people, if their pet idea failed? Maybe as I've heard concerning communism, the problem was not flawed idea but not trying hard enough and not keeping enough orthodoxy? Or just in case always good explanation that idea failed because of some impressively vast conspiracy?
4) What about people with varied brilliant ideas? Should maybe such province be divided in to a dozen of experiments?
(Or maybe such idea is not worth fuzz because it would neither provide a safety valve nor let worthy ideas being tested?)