The 2 "solutions" to the F-135 problem are to (a), bed in the abradable seals i.e. in a tightly controlled operating environment - which implies operating limitations until bedded in, and (b), pre-cutting wear channels in the abradable seals - which seems to negate the entire point of an abradable seal. The root cause still lies in determining if the core shaft flex (due to inertial and gyroscopic forces) will cause a reoccurence of the friction and excessive heat during "normal" operations and manoevers.
Just how much material can you remove during weight saving measures and still maintain the required rigidity of the design? I'm sure someone at PW is pondering that question. The way to get it out of spotlight and get to IOC would of course be to impose a restricted operating regime that avoids the engine problem all together but creates an artifically benign operating environment. I'm sure no-one would even consider that.