Imho you are undervaluing how big that 3% more healing may be for chakra coordination in specific lineups.

Personally speaking i think that talent is the most undervalued talent there is in game right now, even on its basic version.

Yep, but you put it in 'bad' even if now we have in game the trials of sage naruto, sage jiraiya, wb asuma and ninjas like roshi edo tensei now are easy to get for free and they may heal multiple times per round every round your ninjas thank to that talent.

Just think about, for example, a lineup like edo yagura, kushina habanero, edo roshi. Using chakra coordination means you are immortal until wind main or edo roshi are alive.

The same is for something like edo hashirama, sage naruto full sb, sage jiraiya full sb,where jiraiya and naruto will heal two targets per round each one every round thanks to that talent, without doing anything, and by a very huge amount (15% hp on a 40k hp ninja are 6k, it's comparable to water main standard attack just done without using any mystery or standard attack).