it's not Barcelona who is strong this season but Real Madrid who is inconsistent so that this is put to good use by Barcelona to continue to keep the gap between points on the La Liga standings board.
now it is almost certain that Barcelona will win the La Liga title this season and it seems that Real Madrid will focus on the UCL and Copa Del Rey, they are more likely to get it.
and regarding this season's UCL semi-final match between Real Madrid and Man City, I think it is profitable for Real Madrid because they will only focus on that match while Man City must compete with Arsenal currently in the Premier League standings.
Real Madrid lost a bit of their performance in Laliga maybe they are more focused on preparing for the Champions League, it can be seen from the last few matches in Laliga maybe they are not very consistent in their game, 11 points behind to catch Barcelona I don't think they think too much about rushing to be able to catch him, considering they have to focus on the semifinals of the Champions League which met with Manchester City.
I think it is more than obvious that Real Madrid is putting all the physical and mental emphasis on the Champions League and on the Copa del Rey competition. Anything else would, frankly speaking, not very smart. Usually the fans want to get to see the best possible in every single game, but I am sure that all the Real Madrid fans have long understood the situation what this season is all about. The La Liga title has been lost several weeks ago and at the same time Real Madrid is showing top performances in both the Champions League and the Copa del Rey. If I were a fan, I would be all for their strategy. Don't play embarrassing soccer in La Liga, but save your energy for the serious games in the other competitions.