SVRy: How fast did they go?

Spent some time this evening studying some conductor reports from July 1 of 1925. Here is a bit of what I learned about Train 1 which was the daily westbound pass. train. The following times include a depot stop of unknown length so actual speed should be slightly higher than calculated. Leave Baker at 8:00Am and leave S.Baker 8:08 min speed for the one mile distance would be 7.5mph.
S Baker to departure from McEwen 60 minutes for 22 miles =minimum 22 mph.
McEwen to Sumpter 6 miles in 32 min. minus a recorded 15 min. delay to wood up at S Wye = minimum 21 mph.
Sumpter to Larch 7 miles in 40 min. = minimum 10.5 mph.
Larch to Whitney 8 miles in 30 min. = minimum 16 mph.
Whitney to Tipton 8 miles in 26 min. = minimum 18 mph.
Tipton to Austin 8 miles in 29 min. = minimum 16.5 mph.
Austin to Batesville 1 mile in 5 min. = minimum 12 mph.
Arrival time to Batesville is stated at 11:50 making the 60 mile run time in 3 hrs 50 minutes less the 15 min. delay at S Wye for Wood = 3hrs 35 min. or minimum average speed of 17 mph. There are 7 potential depot stops and I am unsure as to how much time would be consumed by these stops. Figuring 5 min. per stop would consume 35 minutes making the average speed 20 mph. If you figure 7 minutes per stop it would put the average at 22.
Train 1 continues after lunch on this day with the same engine (50) but with a crew out of Austin for the run from Batesville to Prairie City.
Train 1 leaves Batesville at 12:30 arriving at Dixie at 1:10. This is 8 miles in 40 minutes for a speed of 12 mph. This is based on arrival time, so should be a good snapshot of speed going up a steady grade.
Train 1 leaves Dixie at 1:17 (note the depot stop was 7 minutes) and arrived at Prairie 2:00PM which is 12 miles downgrade through many 24deg curves in 43 minutes for a speed of 17 mph. Actual speed was likely a bit faster as the 43 minutes included time to negotiate the 2 switchbacks.
If we go back to the run from S.Baker to McEwen which likely would have had the the least gradient and some long tangent track and we deduct 7 minutes for the depot stop a McEwen, average speed goes to about 25mph. Even if engineers dusted out the cars once in a while, it doesn't look like normal speeds wouldn't have been much over 30mph at any time and probably seldom that high.
FWIW, the engine this day on train 1 was #50, consist from Baker to Sumpter was Mail 5, Combine 10 and Coach 26. Sumpter to Prairie was Mail 5 and Combine 10 with the Coach being left at Sumpter to be picked up up by the eastbound passenger, train 2 which on this day was powered by Eng. 1.
This day is nontypical in that Eng 50 ran through to Prairie tieing up at the end of the day after running as EX50 back to Austin. Eng 1 started out the day on train 3 the westbound freight out of Austin to Prairie returning with train 2 tieing up at Baker/S.Baker. Normal operation seems to have been that the engine on the Austin Prairie end worked that district while the Engine the left Baker in the morning with Tr. 1 returned to Baker with train 2. Perhaps 50 had been down to Baker for repairs. Too bad we don't have the reports from the previous several days to see if 50 was in service.