If most halt DHQ/MJY then its rare for train banked till BZU & if happens, Banker must return instantly citing parking issue at BZU!!
Freight will not stop for banker but signal clearance coz Freight Block at MRY (but at Loop not Mainline). Detached banker could be held for a while instead of trolling clashing schedule of M/E/Freight (too rare although) & can be attached citing Signal Clearance!!
GDYA-BZU, 37 Kms: 02591-40 Mins, 02589-49 Mins, 02645-52 Mins, 01046-43 Mins, 06094-43 Mins, 02616-36 Mins
BZU-GDYA:...
more... 08237-55 Mins, 06093-61 Mins, 01045-40 Mins, 02295-42 Mins, 02721-41 Mins, 02615-39 Mins, 02578-50 Mins, 02646-37 Mins, 02522-37 Mins, 02512-37 Mins, 02592-34 Mins, 02590-42 Mins, 2791-43 Mins
There is no much difference in Elevation & Depression run time & if any train get Banker Attach/Detach, it must add 40-50 Mins of Banker Attach-Detach (as per your logic) but none displayed this huge Banker TAT in run-time!!