FYI - I have one that I bought a long time ago as D. crepidiferum, and one that I bought more recently as D. glomeratum, and the only differences that I have ever been able to see are that the crepidiferum grows strictly upright, bigger overall, and the glomeratum grows horizontally to somewhat pendulous, with thinner canes. The glomeratum may have slightly smaller flowers, but it's not much of a difference. I grow them both intermediate to cool, no rest to speak of , just a slight lessening of water when they are in the coolest conditions in the winter. They are both in bud now, but can bloom at almost any time. My opinion is that they are both the same species, and I think glomeratum takes precedence. Orchid taxonomy - -ain't it grand!
Tucker