I really have no clue as to the problem. In my own work I have never used a 11X14 drum for processing 8X10 film, but I have used one of the same diameter and with the same internal configuration to develop two sheets of 7X17 at a time.
As far as I can determine your procedures are virtually identical to mine.
Are the streak lines on the outside of the film (facing the drum) or on the emulsion side (facing in)? The question assumes that you loaded the film correctly. However, given your description of the process the only possibility that enters my mind is that you loaded the film incorrectly, with the emulsion side facing the wall of the tube. If you were to do this it would certainly result in the patterns that you descriibe. Otherwise I have no way to explain the streaks.