I know I probably sound like a broken record here, but I think the most successful parents are the ones who find the good middle ground. I.e., giving their kids certain freedoms and responsibilities but reigning them in on others. I think it also depends on the type of kid you have. If the parent knows they can trust said kid and they have proven so, then they might be more inclined to get more freedoms. If you have a wild child per say, then it might be smarter to keep a tighter leash on said kid.
I have seen time and time again kids with strict, overbearing parents often are the biggest problem cases. But they are experts at hiding it. They may put on the perfect student, polite, "kid with no flaws" mask for their parents and the public, but they spend Friday to Sunday drinking their asses off, smoking and snorting anything and everything they can get their hands on, and doing crazy shit. Some of the so called perfect kids that grown ups see as the "good kids" are absolutely no different from the "bad kids", they just hide it better. This happens all the time in white suburbia. Parents put so much pressure on their kids that they go crazy on the weekends and in their private lives just to get a little bit of a break.
For example, lets take my AP US History class. There was 50x more cheating in that class then any other class I have ever been in. Why? Because most of the parents of those kids in that class expected them to be brilliant, A+, Ivy League bound students when some of them weren't. So they felt like they were forced to cheat because their parents would not accept anything less then perfect. Most of them too were hard weekend partiers and smoked a ton of weed and two were even weekend coke heads.
The most important thing, I think for a parent to understand, is to have realistic expectations for your kid. Every parent wants a straight A, Varsity sports captain, perfectly behaved child. But the reality is, most kids aren't and I think parents have a hard time accepting that. So please, parents, set realistic expectations for your kid or you will only set you and your kid up for future problems.
I'm not quite sure if I answered the question or not, but I tried.