People think that a long climb effort (5 minute) has a bigger peak watt effort, than a smaller humb (1 minute effort) - but it's the other way around. You can power your way through a 1 minute effort, but you need to dose that 5 minute effort and hold back the horses.
But with a geared bike you set-off with a lower ratio than you would fixed.
If 3/32" is adequate for a HC start, then why bother with 1/8"?
HC have got to be more demanding than, eg, regular road use.