Chelsea and Manchester United this season have been in their poorest forms, finding it hard to secure a point not to even mention a solid 3 points, these slow pace and inconsistent game scorelines though makes for their difficulty in attaining better positions on the league table, Unlike other big teams who are doing efficiently, it'll be difficult for the former two teams to finish in a good stand this season.
The both teams has gone from bad to worst, they have not win any 4 straight matches back to back, this season has been the worst season for them because irrespective of there poor performance last season we can never compare there last season with what they are playing in this season, losing so many of there matches they had upper chances of winning.
Chelsea and Manchester United has the same pattern and you could hardly predict there match because when you will feel is the time for them to win they showed you the opposite.
You are right that Chelsea and Manchester United can be called unstable teams when we believed they could win when playing at home but the opposite happened it's really hard to predict, I still remember when Chelsea beat Tottenham of course no one thought Chelsea would win moreover Tottenham still holds an unbeaten record but after 2 red cards the situation changed drastically Chelsea took control and scored 4 goals, I never forget this moment and I call it a bookie's trap because previously the odds for Tottenham to win were only @ 2.00 normally it's @1.6 because Tottenham is in a positive trend and playing at home so it doesn't make sense if the odds are high.
In the last 5 matches, Chelsea and Manchester have both recorded 3 wins yeah it's better than last month and if Manchester is eliminated from the Champions League then they can focus more on the Premier League at least hunt for European League tickets lol. Meanwhile, Chelsea will close the season without a target maybe they will focus on team observations.