Open World of Tanks\res_mods\0.9.15.0.1\scripts\client\gui\mods\mod_team_hp.json with Notepad++ or some other proper editor (Not Windows default Notepad..)
And find the lines around:
"hpTools" : {
There's 2 bits:
"showRemainHalth" : true,
and
"showPlayersDamage" : true,
As a work around, you can just delete the mod_assist.pyc and mod_assist.xml files out of the \res_mods\0.9.15.0.1\scripts\client\gui\mods directory. Been running like this without any issues.