As for Samarin, he may be better off missing Worlds this season. Reading his recent interviews, I feel that behind his downward trajectory, there are a lot more than boot problems which he chose not to talk about. Whatever the underlying cause is, just let him rest and figure it out with his coaching team, so that he can better prepare himself for next season, when the pressure of bringing back 3 spots will get even greater (because people seldom learn from history ) and room for failure even smaller. If the Fed keeps burdening him with high expectations at this moment, I'm afraid that nothing nice is going to come out of this.
(Another thing that might be a concern: his SP really not going well lately. If this trend continues at Worlds and he drops out of the first two groups, the damage to his PCS is going to limit the ceiling of his score in FS, regardless of his performance, and may have influence further into next season. Worlds is in Canada this year. Basically any Russian skater there should be particularly careful...)
(Another thing that might be a concern: his SP really not going well lately. If this trend continues at Worlds and he drops out of the first two groups, the damage to his PCS is going to limit the ceiling of his score in FS, regardless of his performance, and may have influence further into next season. Worlds is in Canada this year. Basically any Russian skater there should be particularly careful...)