My first 2 experiences on a road bike were to test ride the 2003 Lemond Wmns Tourmalet, and the New Specialized Dolce Comp. The Comp has these Zirtz inserts that are for shock absorption - which is probably why it was smoother to ride. It's a more expensive bike as well, but- go figure - those were the only 2 women's bikes they had for me to compare, so probably not a fair comparison.
My bf actually rides a Lemond road bike with a steel frame, and says the steel makes for a smoother ride, so it's possible that the bike, since it was hanging around for 3 years, needed some adjusting.