When btc gets a dump, and the same microsecond the alts get a dump as well, it cannot be people being greedy/fearful, right? it must be a coupling in some form to the mastercoin, btc?
im not saying anything about the intrinsical value of an alt itself, nor if its a good or a bad alt, but just these fluctuations intrigue me and i dont really understand...
Not sure I understand your question : the answer seems self evident :
There is trading constantly on multiple exchanges 24/7, every second of the day. The alt prices (on coinmarket cap or whatever) are based on 'last trade' for a number of exchanges. The trade is in BTC, that is converted to $$ in the quote. If BTC $ price changes, then so must the alt $ price, even if there is no further trade.
If a bid/offer is hit then the BTC price changes as well.
i appreciate the explanation, and it seems fair in regards to $$ value, but thats not what i meant, and thats also the part i dont understand.
When bitcoin makes a pump or a dump, the alt varies in BTCprice as well, and thats strange to me. (as your explanation (as far as i understand) states the $$ price must go up and down seems logic as the BTC value varies in $$ value. That makes sense. But why does the BTC value of the alt change so much as well?? Thats double... For instance: when BTC takes a drop of 10% in $$ value, the ALT makes adrop of 10% in $$value (logic), AND a drop of 10% in BTC value as well (unlogic), makes a total devaluation of that coin of 20%..)
The user BTCMILLIONAIRE explained what could be the cause: When it is clear the BTC is in a downtrend you could get profits by shorting altcoins for fiat: