To some extend I’d say it is, maybe even more so for female hurdlers. I’m sure that Lolo Jones in 11.20s 100m shape would be faster over the hurdles than Lolo Jones in 11.50s shape.
Her 100m PB is 11.24, from 2006, but she only ran 11.49 a month ago.
In 2005 she ran 11.59 flat and 12.76 over the hurdles. One year later, her flat speed had improved to 11.24 and her hurdles time to 12.56.