I remember when I was little my mother using washing up liquid on my hair rather than shampoo. While I think this might be an idea for greasy hair it isn't ideal for other hair types as it is supposed to cut through grease and could strip the hair of natural oils. What do you think?
I do not think that I would since like you said it could strip your hair of natural oils. I am not sure just how different the ingredients are between the two. I am very particular about my shampoo since my hair tends to be a little on the dry side. But then again, one brand is gentle enough to use on animals to wash oil off of them when there is an oil spill so maybe it would not be that bad.
I tried this one time and the result was not nice. I have dry hair and my supposedly gentle lemon based dish-washing liquid seemed to wash my hair shine right out! Maybe it might work for a different hair type but if you have dry hair like mine, please stay away from anything that is not shampoo for dry hair. Do not use bath soap to wash your hair (I have also tried this a couple of times, bad idea) and do not use bath gel either.
I have tried using dishwashing liquid to wash my hair once before because I had run out of shampoo. I couldn't use the bath soap because all it would do was to show up the oil in my hair, therefore, I tried the dishwashing liquid and it was okay.
I would never use washing liquid to wash hair as it is very harsh and not at all suitable for our hair. It would strip our hair and scalp of natural oils and also damage hair.