Rather than trying to beat Hamilton in a head-to-head fight, failing miserably and then allowing himself to be tormented by finishing second every weekend, Rosberg—according to our logic—should have exploited his long-held status as the most intelligent, numerically driven performer on the grid and taken a more pragmatic approach.
Like a football manager guiding their squad through a long, hard season, he should have accepted that there would be days when he would not come close to Hamilton, one of the most naturally gifted drivers of his generation, and adjusted his expectations accordingly, picking and choosing his battles with care.
He should have identified a number of grands prix, particularly at circuits where his Mercedes team-mate has been traditionally weak, he could win, and pinpointed those when the runner-up spot would resemble damage limitation, when second place would not be a sign of inferiority but part of a much wider plan.
Admittedly, such a philosophy would have left Rosberg competing more in hope than expectation, praying Hamilton would suffer a retirement or two along the way and clinging to the idea that, come the end of a 19-race season, it would be him at the summit of the drivers' standings.
But at that point, on the day he qualified more than half a second behind Hamilton at July's Hungarian Grand Prix, it felt like the only way Rosberg, short on confidence and seemingly out of ideas, would ever stand a chance of winning a world championship.
Just four months on, however, his recovery—his transformation—is rapidly nearing completion.
After his morale-boosting yet rather predictable victories in Mexico and Brazil—the first at a brand-new track, the second at a venue where Hamilton has failed to win in nine visits—this weekend's season-ending Abu Dhabi Grand Prix was bound to offer a clearer indication of the extent of Rosberg's resurgence.
Like the Hungaroring, the Yas Marina circuit is among the tracks where Hamilton has always performed strongly, setting two pole positions and winning on two occasions (he missed out on two further victories in the 2009 and 2012 races due to reliability issues) in six appearances.
As such, it appeared this weekend would be the ideal time for the supposedly natural order of 2015 to be restored, for the season to end the way it started and for Hamilton to cap what he told BBC Sport has been "without any doubt the best year of my career in terms of my driving and overall performance" with one more victory.
Indeed, Rosberg himself seemed ready to be put back in his place in Abu Dhabi, telling Motorsport.com's Pablo Elizalde that the "extremely old engine" fitted to his W06 car was "costing (him) straight-line speed" and had left him braced for "a difficult weekend."
Although he had beaten Hamilton in the second free-practice session, Rosberg added that his team-mate was yet to "show his pace on one lap," claiming it was "clear that he still has some reserve."
But the widely expected onslaught never arrived.
Despite his fresher power unit and his impressive record at Yas Marina, where only world champions have triumphed in the race's history, Hamilton was unable to establish an advantage in excess of 0.2 seconds in the opening segments of qualifying, per the official F1 website.
And Rosberg responded in a Lewis-esque manner, saving his best lap for when it mattered most and hurling his car around the tight, twisty final sector to claim his sixth-consecutive pole position.
His pole lap—a resounding 0.377 seconds faster than Hamilton's final effort, per the same source—was almost an act of defiance, confirmation that Rosberg will no longer timidly fade away or hide behind a list of excuses whenever the odds are against him.
With the title already settled in Hamilton's favour, the absence of championship-related pressure has almost certainly played a key role in Rosberg's return to form in recent races.
But the importance of entering the winter break "on a high rather than a low," as he told Sky Sports' William Esler, is huge ahead of next season.
Should Rosberg claim a third successive victory for the first time in his career at Yas Marina, the ghosts of 2014, when his title chances evaporated with a mid-race technical problem, will—as noted prior to the race weekend—be laid to rest, freeing him to start afresh in 2016.
And without that burden—something Rosberg seems to have carried with him for much of 2015—the German can enter next year with his confidence at its maximum, knowing he can take on his team-mate and succeed, with no need to resort to desperate tactics and return trips to the drawing board.
If he can beat Hamilton in Abu Dhabi, he can beat him anywhere.