I agree about the delay when entering tab. There is no need to check it on the server, because the presence of performance points is also checked during the use of songs. Why double check? Healers should work quickly, but this problem only gets in the way. I also find it wrong that all other healing classes have skills…
If the player's HP is below 50% then the second part in the Sheltering Etude description in meaningless because the player cannot be under the effect of the Sheltering Etude.