Hi Peter, What you say here makes sense...however if I can throw a little information into the topic.
I can only go by my own experience in British framebuilding, but when I started my career in May 71 I can't really recall us [Bob Jackson's] using anything other than Campag 1010 long road dropouts, and I think in the early days theses were the ones with the small hole above the pivot hanger. We also had the stamped Campag vertical dropouts.
I do know we had Chater Lea track ends, as well as the long 'Holdsworth style track end'....and of course Campag track ends, which used to be a little longer than the later ones. However, we may have had a stock of plain rear ends, perhaps Agrati, for frame repairs if that's what was required......as well as the Campag derailleur hanger for brazing on rear ends that didn't have such a hanger.
I think the orange Holdsworth in question is simply a cheaper 'clubman' type frame......the red one looks to be better quality, but the forks look to be a replacement pair of a later date?
Cheers
Kevin Sayles
Bridgwater Somerset UK
E-bay
> Versatility as you say. That eBay no-hanger Holdsworth is said to be
> 1970s. Until Campagnolo style derailleur mounting won out, I speculate
> that it wouldn't be a given that every British buyer would want to fit
> only those few rear derailleurs that thread into Campagnolo dropouts. If
> that Holdsworth was made in early 1970s, then derailleur mounting
> versatility may well have been a consideration. British Cyclo Benelux rear
> derailleurs do not fit into Campagnolo dropouts, Cyclo Benelux having made
> their own dropout with hanger. As you know, Simplex differed from
> Campagnolo, as did Huret. Back then, it may have made sense to build with
> no derailleur hanger to allow the owner to fit whatever they wanted. By
> the late 1970s, one would expect derailleur mounting to have settled in
> favor of Campagnolo style (?).
>
> Peter Brueggeman
> La Jolla California USA
> 4peebee(at)peterbrueggeman.com