After Trivandrum-Chennai exp that leaves Salem around 5 AM [before 5 am], there is no train to chennai till 8 45 am when the intercity comes from Coimbatore.
If an intercity exp is introduced between Salem-Chennai around 6 AM stopping at Bommidi, Morappur, Tirupattur, Jolarpet, Vaniyambadi, AMbur, Katpadi, Arkonam then it will run to full capacity as many office goers from Salem to Tirupattur / Vaniyambadi and also from Jolarpet - katpadi will be benefitted.
Also the bus from Salem to Tirupattur takes around 3...
more... hours with bad road conditions.
The same train may be made to return to Coimbatore starting from Chennai at 1 PM to reach Coimbatore around 8 PM which will benefit those reaching coimbatore.
The tain from CBE to Chennai Intercity may be started around 3 pm to reach salem around 8 pm