Again, I think your phrasing is too negative, so let me put it in a slightly different perspective.

First of all, if you sell only a thirth of your holdings on a day that the price is rising over 10% you are not dumping, someone else is buying. For liquidity it would be better if people put their coins up for sale, but if someone is bidding up the price, at some point someone is going to be satisfied with the offer and a trade is agreed upon, after all this is a free market.

Second I would like you to imagine that the person who was buying was actually in it for the long run, like most other participants, with the goal to educate the Dutch citizens. Why would he be buying today so he can, as you call it, dump for a double profit in 8 months? I think it makes way more sence if my last responce to you was picked up by someone who believes in that and is going to ride the wave all the way to a euro.