Play a warzone now and then.
Never once have I seen any player top heals and dmg. I'm at 41 valor. Played a few warzones.
I could probably top 200/200 with my SI by spamming heals on full health team mates while there is no enemy in sight to toss lightning at. Again, this would require me to be healing teammates that don't need healing. I could also throw out the AOE heal any time I see a group of team mates standing near each other even if they have full health.
As a dedicated healer in warzones in premades or in pugs I rarely heal for more than 300k. Maybe once in say 15 matches. If I'm hyrbriding dps with healing I'll generally end up around 100/200 dmg/heals. And even then it requires a Voidstar match where my side is essentially dominating and holding the other side at one objective set for a prolonged battle where there isn't much running around.