Thanks, John, for this heads-up on the 'glider and the Mercury. I'll bear your advice in mind when I set up the 'glider on my new Mercury in May. I'll have to do some plastic surgery on the 'glider in any case, because I plan to run a 36T chainring; and, from my experience with the Raven, had expected to nip off a corner from the rear section in any case.
The Mercury will have a pair of Velo Orange fluted Zeppelin mudguards, 650B x 52mm. These have worked well on the Raven, and the tires on each bike are 1.6" Marathon Supremes. Photos on all that to come in due course (i.e., late spring/early summer).
Am writing this from Down Unda--the Gold Coast in Queensland, where we're visiting our son and his family. I've brought my derailleur bike for some day rides, but over the last 36 hours we've had some 400mm of rain (no typos pls note!), so no riding just yet.
Cheers, John