stability of a coalition: if there is a Left coalition, it is a plurality of 1 seat (44 G&NDP vs 43 BCL), which is inherently unstable as they cannot even appoint their own speaker or lose 1 seat for any reason (illness, death, scandal, going rogue, cross the floor etc).  That is what I meant by unstable with plurality of 1 seat.  If the Greens and BCL would coalesce, it would a plurality of 5 seats (46G&BCL vs 41 NDP), which is inherently more stable - they can choose a speaker from within and afford to lose a  MLA or 2.