this solved my lag problems so I,d thought I would share it with you

Customer Service Representative

Hey there,

Thank you for contacting our support here at Blizzard I'm sorry you've had to wait for a response.

If this issue just happens on boss fights and such, please try typing the following command:

/run SetCVar("raidFramesDisplayIncomingHeals",1)

Should you have any other issues or questions to ask then please do not hesitate to contact us again.

Thank you again for getting in contact with us and I hope you have many epic adventures

Best wishes

Game Master Frelnaars
Blizzard Entertainment