Having some similar thoughts about the altcoins and bitcoin relationship. However have guys noticed that there was time when bitcoin use to go up and then rest of crypto coins used to go down in the market value. This relation was explained with inverse proportionality of the bitcoin and altcoins. This is because whenever there was news that bitcoin will be hard pump soon then people used to sell out their altcoins and buy more and more bitcoin Thus it lowered the value of alts and increase the value of bitcoin and this all was natural. Now a days, whenever bitcoin grows then alts spike too and vice versa. Not sure what is causing the altered relation.