2014 Cowboys that started their career with the Cowboys: our entire starting offense (was originally going to make a list... but... really... it's just everyone including most of the backups), Lawerence, Crawford, Spencer, Lee, Hitchens, Carter, Wilcox, Church, Scandrick, and yes Mo.
2014 Cowboys that started off somewhere else: Mincey, McClain, Melton, Durant, Carr.
We turned that into a 12-4 team, and of 3 (or 4 depending on how you feel about Melton) of the 5 guys in the second list were small, short contracts to players that they thought might work out well. Look at most elite teams and you will see something like this (yes the Seahawks did pay a bit for Avril and Bennett, and the Pats got Revis to a 1 year contract, but that seems to generally be the exception rather than the rule with those teams). That is why I say build through the draft.