It sounds like you are not trying to justify bicycle commuting, but, rather, NOT bicycle commuting. As a senior manager, I might have problems with an employee whose' work schedule varied with outside temperature. I think you have two courses of action:
1) Ride in when temperatures fall below -25 C. Other commuters do ride in those conditions. They manage to solve problems with brakes and gears and operate normally. Drum or disk brakes, internal gears or singlespeed, and low temperature lubricants are all mentioned as solutions on the icebike list.
My commute is only 10 km, and the minimum temperatures here rarely fall below -18 C. Consequently, I can't just say, "I do it and you should, too", because your commute can be far more demanding than mine. That brings us to alternative 2):
2) Drive your car in under conditions when your bike fails to work.
The bottom line is, yes, depending upon your work situation, you well may be off-base. If you want to work from home sometimes, that is a separate issue.
Paul