Bob had some not so: Stupid questions:
1.) Noticed something in the photos of the Della Santa frameset which brought to mind something which I never understood. Is there a reason for using horizontal dropouts on a modern road bike frame built for use of a rear derailleur?
Call me lazy, but I really hate fidgeting with the rear wheels on my old bikes - especially those (now most) which have mudguards fitted.
.
I sez:
Hey Bob I'll answer question 1 I'm sure there are many more knowledgeable folk who can answer your second question with more information than I can provide.
I had a custom made road bike made in 2007, with horizontal dropouts for a couple of reasons, The esthetics's are appealing to me, and I don't really find it too fiddly, as I'm not swapping my rear wheel much. But the main reason I specced them was for versatility. I love the fact that I was able to run this bike as a fixed wheel in the spring. That was my main reason. Seems lame maybe, but it worked for me. I too run fenders, and don't find it to be too much of an issue, again I am usually changing out the rear wheel because I have a flat, I just have to remember to put the wheel back in before I pump it up.
http://www.flickr.com/
I am also currently having a custom cross bike being made by Sam Whittingham, of Naked Cycles fame and I have specced that with horizontal dropouts too. Again, versatility and I want to be able to run it singlespeed for a particular cross race, so long horizontals make sense. So yeah, for me the reasons are why not? I get more versatility this way, with very few downsides.
YMMV
Rodd Heino Ottawa Ontario Canada
oh and some of my trousers have buttons.