If you are travelling to Thane in the down direction during morning peak hours(7 am to 11 am) , never take the Thane local (locals having their destination as Thane).
The same train goes back in the UP direction as CSMT local and hence there is maddening crowd waiting at Thane to get onboard. There is a big chance that you wouldn't be allowed to de-board.
In addition to this, the Thane locals depart quickly from Thane during morning peak hours as the Turn Around Time is very less and the train...
more... is late on most occasions.
Take any other train having a different destination. It is the opposite direction during morning peak hours and hence wouldn't be crowded.