The issue being discussed is that there will be more trains for Circle and North East lines. In this way, it will boost capacity and will ease congestion. There are 47 trains in total on the Circle Line now, at the moment, commuters wait an average of 3.5min during peak hours for a ride, this will be cut to 2.7min. During off peak hours, commuters would only have to wait for an average of 5 minutes instead of 7 minutes last time.
After reading this article, I think that it is necessary to have more trains. Although I do not take circle line everyday, but I knew that the waiting time is very long and the train is always very crowded. When there are more trains, people do not need to wait for that long and the train will be less crowded. This will help people to be more efficient at work as congestion makes people fatigue and unable to concentrate with their work. I hope there will be more trains on other lines in future.