All things being equal, the most valuable position on a team is QB.
Any 1st round pick/selection is based on potential ~ whether DL, QB, OL, etc. There are no guarantees on any player drafted.
Given Romo's age & reoccurring health issues, why is it not foreseeable to draft a potential franchise QB (whether Bortles, Bridgewater or Manziel)?
Moreover, the bad contract Jerry gave Romo last year should not preclude the selection of a QB at 16 (Dallas drafted Dez in '10 when Roy Williams and Miles Austin had 'bad' contracts).
Take the salary cap hit in 2015 (or find a team willing to trade for Romo and re-work his contract to facilitate the transaction) and move on.
If the choice is between Jernigan, Zack Martin, Shazier or Manziel, go with the QB.
Regardless if Dallas does not select a QB at 16 , Dallas should be looking at QB's to draft in subsequent rounds.
It is not uncommon for teams to transition to a new QB ~ San Fran moved on from Alex Smith, Seattle moved on from Hasselbeck, Eagles moved on from McNabb, Carolina transitioned from Delhomne to drafting Newton, Falcons drafted Matt Ryan, Green Bay drafted Rogers, Skins drafted RGIII, Rams drafted Bradford, Lions drafted Stafford.
Is it not best to be proactive rather than reactive?