Yes, It is important.
So, your pool water is perfectly clear. Is it really necessary to check the water balance and adjust it as needed? After all, the water looks great, how can there be anything wrong with it? YES, it is necessary!!!! And clear isn’t the end all. I have seen many a pool that has perfectly clear water that when the water is tested has an incredibly low pH and total alkalinity. The pool is crystal clear because the chlorine actually works better at a lower pH than at a higher pH. But the low pH is more uncomfortable to your eyes and skin and it can damage other pool components. Want a perfect example? I remember on a few of these pools making the comment to the customers that I had just found their pool heater’s heat exchanger. It was dissolved and floating around in their pool as the low pH and alkalinity destroyed it. The copper test of the pool water proved that point. They might not have known it yet, but they soon would when the heater was leaking and no longer functional. So, while they were happy that their pool water was so crystal clear, they were kind of bummed that their heater was trashed due to improper water chemistry, an easily prevented problem with a little testing an adjusting. So YES, it is necessary.