It seems there was never more than one passenger train daily between Alamosa and Durango, although in early years it was a through train from Denver with Pullmans and some schedules show it running at least part of the trip in the dark. For some time the passenger train actually originated/terminated in Silverton, but there was not RPO or parlor car service north (west) of Durango. I have also read where the Silverton "extension" of the schedule was only run in the summer months.
There is also shown a daily mixed train running on the route, generally taking all day to get from Alamosa to Chama and from Durango to Chama. I believe this was in reality a "scheduled" freight and the passengers - if any - rode the caboose
From what I can figure, an average freight train of the early 1900's was 15-20 cars long and pulled by two locomotives. With two more engines cut in to climb Cumbres. If a daily 70 car train was accomplished with C-class power, they would need to run 4 trains a day to move the same number of cars, plus helpers. A lot of power and people were needed.
I guess the question to be asked is did they run more than four freight trains a day between Durango and Chama and between Chama and Alamosa?