Those arguing to make the initial announcement of Paul's gospel the salvation of all are importing the salvation of all into it because they already know about the salvation of all and it's the most important thing to THEM. They are forgetting that Paul's gospel is first and foremost personal and that the salvation of all would be, at the time of Paul's presentation, the last thing on anyone's mind.

The first thing on anyone's minds would be precisely what the Philippian jailer said to Paul, "What must I be doing that I may be being saved?" Paul's answer is not, "Believe in the salvation of all," but rather, "Believe in the Lord Jesus." He would then explain the death of Christ "for our sins."

Has anyone seen the movie "Sully" with Tom Hanks, about the U.S. Airways pilot, Chesley Sullenberger, who landed a passenger jet in the Hudson River in 2009 with 155 people on board after losing both engines due to a bird strike? Everyone survived, but at an FAA inquiry following the flight, Sullenberger faced criticism after simulator testing showed he had time to turn the plane around and return to LaGuardia airport. Why didn't he?

It was determined that the simulator pilots, knowing ahead of time what was going to happen, turned around IMMEDIATELY after the bird strike and made it back to the airport. What the simulator exercised failed to account for was the approximately ninety seconds of assessment time required by Sullenberger and first-officer Jeff Skiles to, a) figure out what happened, b) weigh options, and c) settle on a course of action. When the ninety seconds of real-time human deliberation was taken into account, NONE of the simulator pilots made it back to the airport.

This is what is happening with those who think Paul's first announcement of the evangel is an announcement of the salvation of all. While the truth of the salvation of all can be deduced from an appreciation of the sufficiency of Christ's sacrifice, it is not the first consideration. (An honest and context-driven assessment of the word "our," as in, "Christ died for our sins" would show that.) They are importing the salvation of all into the initial thrust of Paul's announcement because they already know the salvation of all and it is THEIR first concern; it is the most important thing to THEM. They are not in the room of the Philippian jailer with Paul in real-time, where the only concern of the Philippian jailer is his own salvation from whatever eternal doom he thinks awaits the human race.

Without this artificial importation of what THEY already know and hold dear, the supporters of this opinion could let the word "our" of 1 Corinthians 15:3 speak for itself. Left to its own real-time devices, the "our" of 1 Corinthians 15:3 refers to the sins of Paul and anyone who would accept his gospel.  

As is shown by his question to Paul and Silas, the Philippian jailer's first and foremost concern is for himself. He cannot yet extrapolate the evangel into its full possibilities—even though the possibilities are inherent in the evangel.

This is where, in my hypothetical scenario, the jailer suffers a heart attack. He dies as a member of the body of Christ (he has accepted the evangel for HIS sins), but has not yet had the time (or the desire, frankly) to practically consider the far-reaching repercussions of the evangel and reverse his position on the fate of ALL humanity.

Thus, it is POSSIBLE to grasp the evangel for one's PERSONAL salvation, while still believing in either annihilation or eternal torment—if even for a moment. But if it is possible for a moment, then it is possible—PERIOD.

Therefore, it is NOT essential for one to unhand either the annihilation or the eternal torment of the rest of humanity in order for one to believe Paul's gospel for one's own salvation.