I can't understand that.
If you had been C/F by an expert in his field then there's no reason at all why you had such a bad day.
Unless of course you were daft enough to buy the Mizuno MX200s
Probably a case of over expectation and trying too hard with the new bats. Now the novelty has worn off a bit relax and play within yourself like you did with the old ones (unless of course you couldn't hit those either hence the change )
I remember the first time I went out with my new C/F Mizuno 200's. Driving the ball like God, every single iron shot I hit, whether it was a 9 iron or a 4 iron went anywhere but where I was intending. Fat, thinned, the odd shank, it was awful. I really thought I had made a mistake buying them. Took me a good 3 or 4 games to adjust to them.
I've not had any such problems with the "off the peg" i15's. I guess I was just trying too hard and expecting too much from the fitted clubs.