The first three games of the heavily-abridged Round 13 look too close to call this week, which has made for some of the highest levels of Head-to-Head Tipster disagreement we've seen this season.

To state the stunningly obvious, 2017 has been a year where form has dominated class, in which context Port Adelaide's 70-point loss to Essendon, and GWS' narrow loss to Carlton should come as little surprise.

Six home teams but only three mid-week TAB favourites won their Round 12 games, which has catapulted last-season's spoon-winning Home Sweet Home a tip clear of Bookie Knows Best.

MoSSBODS and MoSHBODS have very similar opinions about the likely Totals in all seven of this week's games, differing by no more than three points in any of them.

Doubtless there are good financial reasons for it, but the commencement of bye rounds on Thursday nights has always seemed a bit odd to me. All the moreseo this week where we also have the traditional June long-weekend Monday fixture, which means that the round's seven games are to be sprinkled across five different days.

Port Adelaide regained top ranking on MoSSBODS and MoSHBODS this weekend after a 51 point and 21 scoring shot victory over the Hawks. It's now rated an 0.3 scoring shot better team than Adelaide at a neutral venue according to MoSSBODS, and a 1 point better team than Adelaide at a neutral venue according to MoSHBODS.

If you'd offered me, on Thursday afternoon, a 3.4 from 6 average for the Head-to-Head Tipsters and a sub 21 all-Predictor mean absolute error (MAE) for the Margin Predictors I'm fairly certain I'd have signed for it.

This week, MoSSBODS and MoSHBODS disagree by more than 3 points about the Total in any single game only for the Cats v Crows contest, which MoSHBODS assesses a 205-point game and MoSSBODS a 200-point game.

For those of us who love the 9-game form of the AFL round, the 6-game version seems like football's T20. (And, yeah, I'm going to leave that analogy alone now because I don't think it'll carry me very far).

Adelaide did more than enough this week to convince both MoSSBODS and MoSHBODS that it was the most deserving #1 team, a position previously held by Port Adelaide on both Systems.

In a season that's been as delightfully unpredictable as this one, I think you have to nod and sagely accept a round where your best Head-to-Head Tipster (Consult The Ladder) bags 8 from 9 and your average Tipster manages 7.

This week, the two MoS and the two bookmakers all expect the average game to produce about 182 points, though they get to that average by different routes.

There are very high levels of agreement amongst the Head-to-Head Tipsters this week, with the only underdog forecasts coming from MoSSBODS and, of all things, C_Marg in their selections of Port Adelaide and GWS, from Consult The Ladder also in its selection of GWS, and from Home Sweet Home in its selection of Carlton. The other 75 tips are all for favourites.

Adelaide, according to MoSSBODS and MoSHBODS, didn't do quite enough in their victory over the Lions to reclaim the number 1 spot, which has now been held by Port Adelaide for the past two weeks.

This week it was the turn of the RSMP Head-to-Head Tipsters to outperform the field, the pair recording the only 6 from 9 performances, which sees them now sitting one tip clear at the top of the Leaderboard on 51 from 80 (64%).

The last two Totals markets were posted much as we expected and left MoSSBODS and MoSHBODS predicting, on average across the entire round, about an extra goal and a half per game compared to the bookmakers.

This weekend's football seems very likely to be rain-affected, which should provide an interesting assessment of the extent to which MoSSBODS' ignorance of weather impairs its practical efficacy as an informer for over/under wagering.

Amongst this weekend's slightly truncated set of eight matches, five have bookmaker handicaps that imply the final victory margin will be under 14 points.

The Crows, after their second successive loss - the latest one to the Dees - have surrendered their number 1 ranking on both MoSSBODS and MoSHBODS. That spot has been taken by their cross-town rivals, Port Adelaide.

Five favourites won over the weekend, and all of the MoS Head-to-Head Tipsters joined BKB in scoring five out of nine for the round.