That would be true if they were direct competitors like Litecoin.  They are not.  They work together.  However, Mastercoin will carry far more functionality than bitcoin.  Mastercoin will finally far exceed bitcoin in value.  Although bitcoin will always operate as the 'currency' portion of the system.  Mastercoin will serve other parts = many other parts.


'overall market cap' could be compared if these two served the same purpose.  They don't.  Mastercoin will perform a different function than bitcoin.  It won't replace it as a currency.  If it were a currency replacement (as Litecoin is) then this comparison might be interesting.  Mastercoin operates to enhance bitcoin - not replace it.  Litecoin attempts to replace it with some added differentiating features (not very interesting).  Mastercoin is not an altcoin.

Mastercoin is not an altcoin.   Mastercoin is not an altcoin.  Mastercoin is not an altcoin.
Say it a few times if it makes you more comfortable.