One of the most frustrating strategies to play against is one where you have a tank self-healer that's backed up by a healer further behind in the lineup. You need to do more damage over more rounds.
If you have your own healer, you might be able to mitigate some of the extra work that you need to do. But usually, healers will grind you down.
Healing you down
In the lower leagues of the Modern league, I've been using a double healing strategy to decent effect. The Imperial Knight as my tank and the Venari Crystalsmith to back him up. It doesn't hurt that the Crystalsmith does a sweet 3 range damage as well.
At the end of round 3, thanks to multiple heals, my Imperial Knight was still at almost full health while my opponent was down to his last card.
Now, one thing that's worth factoring in is the speed of your healers. Ideally, you'd want one to be fast and the other to be slow. Why is that? That's because you want to get a heal at the start of the round and at the end of the round.
If they were both at the same speed, there's a risk that your tank takes on too much during the round that it dies at the start of the following round.
In the end, it was a comfortable victory. You can catch a replay of the entire battle here: https://splinterlands.com?p=battle&id=sl_549ca0c59df5c652bcbc785b34526579&ref=charcoalbuffet
Do you like to use healers in your own battle or do you prefer to do maximum damage instead?