They'll be foolish to do that seeing as they now control the draft.
The next QB needy team to miss out on Manning might be willing to give up a relatively dumb some to get to number 3 and trade up for Tannehill.
Especially after he has one of those seemingly perfunctory exceptional "QB pro-days".
Best Oline for Cowboys:
LT: Free LG: Mankins C: Gurode RG: Holland RT:Young (or an early draft pick)
Hatcher = better overall player than Spears (equal run stopping; better pass rushing)