Just pick ur targets carefully, I do this all the time in gilneas trying to take an enemy node, scout it out for a sec, on my ret other day I 1v3 hunter/warr/enh, u can bet ur ass they wernt the most skilled players and I picked the enh with 120k hp, pop guardian stack holy power wings zealotry repent warr zerg sham down , heal , d cds , hoj warr finish him with cds still up, bubble let hoj come back off cd hoj hunter and eat him gg. Its mostly about having all ur cds(defensive and offensive) and managing them carefully