I have one of these from Rogue Valley Roses and another from High Country Roses. The Rogue PdS resembles most of the photos here--a medium pink with violet touches and even crimson shadings at times. The High Country PdV is consistently light pink.
In an article entitled "Gallica Roses" by Tess Allen in THE ROSE ANNUAL of 1971, Allen makes a clear distinction between 'Jenny Duval' (p.25) and 'President de Seze' (p.26).
According to the article “Variation in resistance to Marssonina rosae (Lib.) Died. among different Rosa L. cultivars and species including three dogrose species (Rosa sect. Caninae)” [Scientia Horticulturae Volume 109, Issue 4, 15 August 2006, Pages 353-360]; 'President de Seze' is very resistant to Blackspot, both in the field and on inoculated leaflets. This resistance was later confirmed in field tests in both Sweden and Canada. [Carlson-Nilsson, U and Davidson, C.G. 2009. A three year study of winter hardiness and blackspot resistance (Diplocarpon rosae Wolf) of roses in two climatically different environments. In Zlesak D.C. (Ed.) Roses. Floricult. Ornamental Biotechnol. 3 (special issue): 138–151]
