DD's DH tells a funny story about this.. His mom was/is one to follow directions
to the letter and if the shampoo says to "lather, rinse, repeat", that's exactly what she does - as well as leave the conditioner on for the
exact amount of time per bottle instructions.. She even bought a special "timer" for the bathroom so she wouldn't rinse the conditioner out too soon.. Used to drive him crazy when he was still living at home and needed to get ready for school or work.. She also has to go through her "lotion" routine for her arms, legs, hands, and face.. - She can easily spend an hour and a half in the bathroom in the morning when she "takes her shower"..
I am in and out like greased lightening..

Even use an Avon shampoo/conditioner combo to eliminate extra steps and wasting time.. I have more important things to do than spend an hour and a half taking a shower - but then again, his DM is the same woman who can't go to the drug store to pick up a prescription without filling a thermos with water, making a half a sandwich to bring along in a baggie, and heaven forbid she's doesn't have a banana to tuck in her bag as well!!

(The drugstore is 10 minutes from her house and she's only going through the drive-thru to pick up a script she called in the day before..)
Oh well - different strokes for different folks..
