This is 100 % wrong, as was already pointed out by 1 person.
What you have seen is if you try to sell at an amount that is “too low”, you will sell at that low price. So you will not get the amount that the item is worth.
However, what you sell the amount for and who you sell the amount to is two different things. The guy with the highest buy order will always get the item, so he will just get it cheaper and be happy. This is why you will see posts in the forum of “Oh this guy sold me an XX for just YY ISK, to my big surprise”.
The same goes for sell orders. You can trick yourself into paying too much, but you cannot decide who to buy from, you always buy from the person with the lowest sell order.
The system has to be this way, in order to prevent people buying and selling items to themselves at artificial prices. Every item on the market would be heavily price manipulated by people like myself if this was possible.
