"Gave some slack" is the phrase used to express giving someone some room to work or act independently and creatively. Some synonymous phrases that can be used in place of this expression include "loosened the reins," "cut them some slack," "allowed some leeway," "granted some freedom," "gave them some wiggle room," or "relaxed control." All these phrases convey the same idea of giving someone some space, trusting them to make their own decisions, and allowing them to take responsibility. It's a positive and empowering sentiment that highlights the importance of trust and respect in any working or personal relationship.