We were running on panracer Hi-roads 26 x 1.5 on our tandem, until just after christmas, when I got fed up with changing tubes by the roadside. All from hawthorn twigs thrashed off the hedges by the mauling machines the farmers use. The final straw (twig?) was when I forgot to take a spare tube (luckily remembered the puncture repair kit), repaired the puncture, put it back in the wheel, started to pump and..psssss. My first repair was good, but we had picked up two holes simultaneously, I think from two thorns on the same twig.
I replaced them with Panracer Pasela TG 26 x 1.75 as a winter tyre.
The extra tread has been useful on wet mud on the lanes, I think, but I have had nearly as many punctures. Now from tiny bits of flint which get stuck in the grooves in the tread. Much like your tiny slivers of glass. The kevlar bit doesn't seem to make a lot of difference. This never seemed to happen with the much smoother Hi-roads, I suppose the flinty bits just bounced off. I was only inflating to the recommended pressures in each case, 85psi for the Hi-roads and 65psi for the TG's.
Any day now, I'll get round to putting the Hi-roads back on, the hawthorn twigs have now rotted away. I reckon we'll gain a couple of miles an hour progress-wise. One from the easier rolling tyres and the other from having been pedalling the extra weight and width around which has increased our strength and fitness.