NSConfinementConcurrencyType context as child of a parent context

Reading Apple doc (http://developer.apple.com/library/mac/#release…), I’ve noticed the following about NSConfinementConcurrencyType:

You cannot use this concurrency type in conjunction with the new nested contexts feature

But in Chapter 5 (Parent/Child NSManagedObjectContext Instances), PPRImportOperationAlt1 class, you do the following:

NSManagedObjectContext *localMOC = nil;
NSUInteger type = NSConfinementConcurrencyType;
localMOC = [[NSManagedObjectContext alloc] initWithConcurrencyType:type];
[localMOC setParentContext:[self mainContext]];

Is this ok?

Thank you in advance.