Doodlebug...
Just a question, what happens if your vertical mode inadvertantly changed from VNAV to V/S unoticed (say from a FMC hiccup which changed the autopilot mode-You diagnosing the FMC...). Sailing through your cleared level? Do you use VNAV for an single engine climb? (so would you remember to change the altitude preselect window to the lower value shortly after an engine failure?). Just thinking of a few 'what ifs' thats all.
Second thing is tonight we had a 'mild' RA caused by another aircraft climbing to a level 1000' below us. Our V/S 500fpm (descending), the TA came when he was 3500' below us, the RA when he was 1700' below.... Enhanced mode S ain't as clever as all that...
And as for VNAV for stepped climbs, what happened to passenger comfort?