Which one would that be why would career expectations in this case be a "long shot" ?

You certainly can't be referring to UAL/CAL as career expectations were indeed a consideration in that SLI. Considering that both of those carriers were considered to be near equals in that merger and that each group (out of 2) brought different, but nearly equal strengths, the SLI in that case looked pretty fair in the award and additionally was able to be crafted in accordance with the applicable merger policy.

Please elaborate.