I think I've discovered the real solution to wheelspin. Don't use the stock Kenda Kwests! 
The fact that in addition to my steep grade issues I was also readily able to spin the front wheel when taking off from traffic lights on level ground did suggest to me the Kwests are not the grippiest of tyres on tarmac (I'm no hugely muscled elite sprinter). So I decided to do an experiment, last night I 'borrowed' the Continental City Contact 26x1.75"s from my girlfriend's bike (the only 'spare' tyres I had handy apart from the Kenda Kwest 26x1.25"s that came on my Bacchetta...) and today tested them out on the Bike North North to West Head ride. Despite not being especially high performance tyres the Conti's gave me much better grip, and while I still needed to emply anti-wheelspin technique I didn't have any problems with the front wheel slipping and this was on a ride which includes plenty of seriously steep bits (such as the top end of Kissing Point Road, which has a maximum grade of 17% :shock.
So, I've concluded that learning the right techniques (getting your weight well forward and smoothing out your pedal stroke) goes a long way to eliminating wheelspin, but if you're going to be riding really steep sections then good tyres are essential too. Now I feel pretty confident in my ability to ride the Sofrider up any grades that I've got the legs/gears for, at least on reasonably dry, clean tarmac
The fact that in addition to my steep grade issues I was also readily able to spin the front wheel when taking off from traffic lights on level ground did suggest to me the Kwests are not the grippiest of tyres on tarmac (I'm no hugely muscled elite sprinter). So I decided to do an experiment, last night I 'borrowed' the Continental City Contact 26x1.75"s from my girlfriend's bike (the only 'spare' tyres I had handy apart from the Kenda Kwest 26x1.25"s that came on my Bacchetta...) and today tested them out on the Bike North North to West Head ride. Despite not being especially high performance tyres the Conti's gave me much better grip, and while I still needed to emply anti-wheelspin technique I didn't have any problems with the front wheel slipping and this was on a ride which includes plenty of seriously steep bits (such as the top end of Kissing Point Road, which has a maximum grade of 17% :shock
.So, I've concluded that learning the right techniques (getting your weight well forward and smoothing out your pedal stroke) goes a long way to eliminating wheelspin, but if you're going to be riding really steep sections then good tyres are essential too. Now I feel pretty confident in my ability to ride the Sofrider up any grades that I've got the legs/gears for, at least on reasonably dry, clean tarmac
