It's a terrific theory, backed up by everything except evidence. Only in North Korea is proof of the Dear Leader's greatness so eagerly taken as a required conclusion to all debate. The truth is that eventual rugby league premiers almost without exception have winning records in their last five rounds, and the winningest round is the fifth from the end of the season – in a 26-round year, that means round 22.

To put it another way: if your team is going to win the premiership, it must win this weekend. You read it here first.

Last year, the Rabbitohs never topped the ladder and finished third before their run to glory in the finals. After a patchy season, it was round 22, this day a year ago, in which they announced themselves as a major threat when they steamrolled Manly 23-4 at the SCG. Manly were competition leaders at the time, but from the night of their dismemberment at Souths' hands they would win only two of their next seven games and go out backwards. Souths' power game, executed to near-perfection in round 22, became the signature of their finals campaign.

The real league season, in a lot of ways, begins this week. The last six premiers have all won in round 22, the only round about which this can be said. You could make that the last eight if you put an asterisk next to 2008: eventual premiers Manly lost 16-10 to Melbourne in that round, but the Storm, as was later revealed, had a big asterisk in their financial accounts. (On that point, the 'shadow premiers' of 2007 and 2009, the dudded grand finalists Manly and Parramatta, both won in round 22 in those years and also had winning records for their final five rounds, as did the fraudulent premiers Melbourne).

The last premiership-winning team to lose in round 22 was Bennett's Broncos in 2006. So does this mean the skinny one's teams habitually fall into a pre-finals form slump? Not on the scoreboard anyway. Far from going into a dip, Bennett's seven champion sides have all been August winners. His 1997 and 1992 Broncos won five from their last five premiership rounds. His 2010 Dragons, his 2000 Broncos and his 1998 Broncos all won four of their last five rounds. His 2006 and 1993 Broncos went three and two.

Going deeper (and is there any depth to which the data-mining league lover won't go?), over the past 25 seasons, only one eventual premier did not have a winning record in their last five rounds, and that was the Newcastle Knights of 2001, who went two and three. Under Andrew Johns and Ben Kennedy, that was the kind of exceptional team that proves the rule. Beyond those Knights, you have to go back to the 1986 Parramatta Eels for a premier with a non-winning record in the final five rounds, and that Ray Price-led team, another exceptional bunch, ended its regular season with two wins, two losses and a draw.

What does it all mean? Probably nothing, as usual. But there is no consolation and no hidden genie for teams that do not start winning games this weekend. Of the last 25 grand final winners, eight went through their last five rounds undefeated, nine lost one game, and seven lost two games (interestingly, these include the winners of five of the last nine grand finals, but they still entered the playoffs with winning balances in August). If winning starts anywhere, it really starts in round 22.

It's probably axiomatic that a premiership winner will have to play well in the final month of the regular season, but it's amazing how logic is put to one side when it comes to the mystique around Kim Il-Bennett. Of course he has earned that through his record, and he is not above garnishing the enigma with some Chauncey Gardiner-like silences and riddles. That magic has all kinds of useful applications, not least of which is the tendency of players and coaches to believe in it. Bennett has a list of achievements that only ever had one caveat, which was that he won six of his premierships with a well-stocked playing list, a one-team city and many other advantages. In winning in 2010 with the Dragons, he showed he could lift a good but not great team to the top. If he can do it this year with the Broncos, nobody can accuse him of merely steering the fastest car to the finish line.

But don't believe all the smoke and mirrors about a preparation that is so clever that it can play with a team's form and deliberately lower expectations. The Bennett pre-finals slump is a myth - unless you count all the other Bennett teams that slumped in August and kept on slumping through September. The eventual premiers will win this weekend, and improve their position as this month goes on. You read it here first.