Whether taking the train to Tibet helps reduce the Altitude Sickness or not?

Experts declare that taking the train travel to Lhasa does not offer much help to against AMS (Altitude Mountain Sickness) because the train is special designed and pressurized to prevent altitude sickness toward passengers. Many Tibet  tourists may have trouble sleeping on the train and feel exhausted after arrive in Lhasa, so normally we suggest our clients to spend at least 2 days in Lhasa before going to higher altitude attractions.