I've just looked back over the previous five seasons. I'm not making any predictions because there's too many variables. It is interesting to look at trends, however.
In four of the previous five seasons, the top two after 40 games were still in 1st and 2nd place after 46 games.
What's the outlier? In 2014/2015, M'boro were top after 40 games and on 75 points. Bournemouth were in 2nd place on 74. M'boro won three, drew one, and lost two of their final six ( 10pts from a possible 18). They finished 4th on 85 points. They then lost in the play-off final to Norwich (who were 3rd after 40 games and still 3rd after 46 games). Watford went up in 2nd.
[Interesting, Bamford was up front for M'boro that day. M'boro had 8 shots, 1 on target. Bamford had one shot.
Howson, Johnson playing for Norwich and Clayton in the middle for Boro].
Context is important. Boro had a tough enough run in that year, even beating Norwich away in the last six games. But the most important factor was the late surge of the other teams. Bournemouth won five of their last six. Watford won five of their last six. Norwich won four of their last six. And it was really tight at the top after 40 games:
1. M'boro - 75pts
2. Bourne. - 74 pts
3. Norw. - 73 pts
4. W'ford - 73 pts
5. Brent. - 69 pts
6. Derby - 68pts
So, 7pts between 1st and 6th (at the moment it's 14pts between 1st and 6th).
The other thing to consider is what other teams are doing. The reality is, if it's tight and those around you are winning games, you have to win yours; if they are dropping points, you can afford to drop points. If you look back over the past five years, this was always the case. You don't really get away with dropping points if others are winning. Although, interestingly, the season after the example above - 2015/2016 - M'boro went up in 2nd, but only by the skin of their teeth. Brighton, in 3rd, finished level with them and it was M'boro's +2 GD that took them up (they only conceded 31 goals that season). In that run-in of the last six games, Burnley and Brighton, who were 2nd and 3rd after 40 games respectively, won the majority (5 of 6 and 4 of 6) of their final games and Boro didn't. Boro had a reasonable cushion after 4o games that season:
1. M'boro - 79pts
2. Burnley. - 77 pts
3. Bright. - 75 pts
4. Hull - 72 pts
5. Sheff. W.- 68 pts
6. Derby - 67pts
So, tight in the top four, but a 12 point gap between 1st and 6th.
Interesting time!