Whimsey, the mechanism is simple enough ... but it requires parts to slide over each other. Therefore, a light oil is needed ... 3-in-1 would work fine, motor oil would too, though it might hang-up in the coldest conditions. I'd also use ATF, MMO and other very-light lubes.
Next time I have the machine in the thank-you-sir-may-I-have-another position, I'll have my old can of Valvoline Synpower spray lube handy and I'll give it another shot ... just to be sure.
Yes, everything seems to work fine now. The unit is almost 4 years old and has seen seldom use. I attribute the problem to long periods of sitting and marginal lubrication from the factory. Annoying when you are in the middle of clearing, but an easy "fix."