Apologies for interrupting, but let me add a point. What you has shared is absolutely true, no doubt in that, but what matters is the state of these trains on the day of journey.
The availability pattern of GR is same throughout the year. You will find hundreds of seats available before a week, but by the time it departs it gets almost filled. For instance, @19:42 18 seats are available in current today, being middle of weekend. By the time it departs, all the seats may get filled. This train is a blessing for last minute travel planners.
Now...
more... regarding JB. The CC coaches of this train has huge demand. There has been a prolonged demand of adding another CC coach to this train, but due to some operational reasons the demand hasn't been fulfilled. Regarding availability in 2S, this train is no different from other intercity trains in India where, there will be many seats available for booking, but a ticket holder has to fight his way to get to his seat in coach amidst the menace of unreserved passengers.
The demand for a day train is genuine.
Thanks for understanding. :)