I tried it not too long ago and something spooky happened. Obviously there's a reasonable explanation for it, but I'm still not 100% certain which is what makes it still sorta spooky.
Anyway, eyes open or closed, things look the same. Dark as h%ck. So I'm washing my hair (fairly long), rinsing it out with one hand after the other. Then on one occasion, I swipe one hand over to slick my hair back and press some water out with my right hand, then the same with the left... then I could swear I felt a third. I stopped everything, eyes blasted open, and just stood there unable to really look around, so just staring wide-eyed.
After a moment of silent reconsideration I just kind of laughed and continued showering, but my imagination was going nuts. Dropped the soap a few times, and every single time while reaching and feeling around the tub floor I silently prayed "PLEASE don't let me feel a hand or something grab back."
So, it was oddly a fun and exciting experience. Would try again. Thanks for the recommendation, OP.