Personally, I think it's a far better way to learn geometry. And a little less frustrating. Some are a bit tricky, though. The student is using logic, and deductive reasoning, to solve a problem, rather than just formally doing a proof. I only mean to offer an opinion that may be different from current popular math teaching ideology.
Proofs also teach the discipline of having a supporting reason for every statement.
A geometric proof is the concrete practice of an abstract thought process. Years later they may not be able to quote the postulates verbatum, but they will demonstrate the same logical sequencing in solving problems that they practiced in Geometry. Proof-writing is the process of writing mathematical thought and it does force one to concentrate on the particulars of your reasoning. I don't doubt that one can learn reasoning and geometry in a number of different ways, but it is often to the student's disadvantage to abandon the more challenging path. They just finished up doing some proofs and I know it has helped her reasoning processes.