If you have missed Charles Cole’s excellent paper delivered at the CMAA Colloquium, on the development of chant at Solesmes from Dom Mocquereau to the current day, it is well-worth reading. It is available for download on his website.
Cole focuses on the work of Dom Cardine, looking at the practical interpretation of Seminology. He highlights several very important techniques that are still regularly misinterpreted. The most crucial is arguably the change to the way we sing the Oriscus in a Salicus (group of three notes.) No, we don’t lengthen the middle note with the vertical episema anymore. He also looks at the horizontal episema and the liquescent.
There is a particularly enlightening section on the use of seminology and interpreting pitch using the Introit for the Epiphany Ecce Advenit.