Heads-up salamander creates a simpleton contest: your straddle against one opposite’s straddle. Add a third participant and the geometry of the hand changes now.
There are more combinations of fresh men in the pot, more draws to report for, fewer strip bluffing opportunities and a greater that a apparently wide one-pair hand is already behind. Decisions that feel subroutine against one opposite can become overpriced when two players stay on interested.