Lots of folks used hangers in the old days, and got fine results; I still do. The trick is to use an agitation method suited to tanks. Here's what Kodak suggests for TMY2- it is typical of what works:
Large-Tank Processing (1/2- to 3 1/2-gallon tank) Rolls and Sheets
"Agitate continuously for the first 15 to 30 seconds by
raising and lowering the basket, rack, or spindle 1/2 inch.
Do not agitate the basket, rack, or spindle for the remainder
of the first minute. Then agitate once per minute by lifting
the basket, rack, or spindle out of the developer, tilting it
approximately 30 degrees, draining it for 5 to 10 seconds,
and reimmersing it. Alternate the direction of tilting the
basket, rack, or spindle."
Tanks want agitation only at minute intervals,
and tilting the hangers as Kodak suggests reduces the chance for sure on the borders.
Lifting the hangers out "every 15-30s to inspect them" is agitating them ! Besides over-agitating the film, you are creating the surge of agitation at the edge of the film.
Unlike using reels in small tanks, here you have a little film exposed to a lot of developer. You don't NEED lots of agitation; 5 to 10 seconds is plenty. Lift, tilt, replace. Easy. Check the Kodak data, use the large Tank times. You don't need to agitate left and right each cycle: tilt to the left one time, to the right the next.
Try to develop between 8 to 12 minutes, so diluting the developer is a good idea. If you don't want to dilute the developer, then pre-soak in water for 3 minutes.
It is a very good technique, but it wants finesse and consistency.