The Druid's HoTs can outheal one Rogue's damage - focus fire the Rogue first, then burst the Druid before HoTs stabilize.
No healer means you lose attrition fights - win in the first 10 seconds or Vanish/reset for a second opener rather than trading.
Blink/Frost Nova can stall your double-opener - Shadowstep to close distance immediately rather than chasing on foot.
Whoever double Cheap Shots first almost always wins - this is a pure execution/reaction-time race with no healers to fall back on.