I have been skimming the posts instead of reading them in depth this week, so forgive me if I am redundant...but I think I may have an insight into a difference between unschooling and relaxed homeschooling.
 
Secular unschooling has its roots in the philosophies of the "enlightened" Rouseau who believed that children were naturally good and had to be taught to sin by a sinful world.  He believed that if a child were not influenced by a sinful world, they would grow up to be good and pure.  Therefore, those who hold to that philosophy believe that a child is raised to follow their own basic good nature, they will choose what is best for themselves and grow up to be better people.
 
Christian unschooling (or as Mary Hood prefers to call it, "Relaxed Homeschooling") believes that children have sinful natures and need to be raised in the love and admonition of the Lord.  However, we do agree that children are perfectly capable of pursuing educational interests with guidance from the parents.  We impose more limits and probably manipulate the learning environment more than an unschooling purest. (i.e.: Christian education is a priority for us.)
 
The difference is that we as Christian parents understand that we are responsible to mold their character to Godly standards, whereas the secular unschooler would not impose Godly standards on their children...but instead allow them to make their own choices entirely.
 
Christian unschoolers may allow their children to make educational choices for themselves, but we never compromise the gospel.  We hold ourselves to that same Godly standard that we hold our children to.  I think this is one of the reasons why Christian and secular unschoolers will never be in agreement and why there is so much friction on secular unschooling lists between the Christian and the unchristian.
 
With this in mind, some Christian homeschoolers use the term Relaxed Homeschooling (or Christ centered unschooling) to clarify that we are not in agreement with Rouseau and that we do not allow our children to follow their own sinful natures without correction.  We do however prefer interest led learning and a more relaxed lifestyle of learning that is similar to secular unschooling in appearance because our children are encouraged to take charge of their own learning and work on their own time table according to their interests and abilities, rather then being forced to fit a mold as traditional education dictates.
 
Whew!  Does that make any sense?
 
Bonni