Fan angst will ramp up as the CBA deadline looms, as will player uncertainty. I remain convinced that all of this is absolutely necessary from the owners' perspectives; their demands are big and across the board for a reason. I don't fear a long-term lockout, but a lockout of some length is mandatory if the two sides are going to see just how entrenched the other really is.
So, what if the draft comes and goes and no CBA has been reached? I personally see that as unlikely, because just as the March 3rd lockout date puts players and free agents in particular over the proverbial barrel, the draft date puts front offices over a barrel all their own. Other than the few big-name free agents every year who get top dollar, most free agent signings or re-signings are of the role player variety, thus eliminating or postponing a team need that HAS to be addressed in the draft. Since teams will be without the ability to re-sign even their own free agents, all 32 teams would go into the draft with more needs than picks. Postponing free agent signings until after the draft would leave agents and players with too much leverage over front offices desperate to fill roster talent deficiencies they were unable to fill during the draft.
So think of it this way: A lockout lasting until roughly Combine time or thereabouts is good for the owners, as that time period will evaluate the real cohesiveness of the players union.
A lockout lasting until after the draft would leave free agents with substantially more monetary leverage when a labor agreement is actually reached. Not to mention that the NFL likely does not want the prime time draft to be dominated by talk of the lockout and the inevitable millionaire vs. billionaire talk, and the always audible average joe complaints about spoiled athletes not being grateful for what they have got, etc, etc, etc.
One other factor: The excitement following the draft is often used to drive season ticket sales in places where fan interest has been flagging due to poor results. No labor agreement will effectively kill those ticket sales.