[QUOTE=ravenclaw;2620439]
Seattle Slew used to be at Spendthrift Farm. When Spendthrift went under, he went to Three Chimneys. Three Chimneys has someone ride their stallions (what a COOL job that would be!!). So maybe there was a change in his behavior once he went to Three Chimneys and started with regular exercise. [/QUOTE]
When Seattle Slew retired to Spendthrift, the original owners stipulated that he be exercised under saddle on a regular basis. He probably switched riders when he went to Three Chimneys, but they rode him at Spendthrift, too.
Last time I visited Three Chimneys (before SJ retired), I was told that they rode all the stallions that were sound enough, weather permitting. They have a nice fiber jogging track that runs between some of the stallion paddocks.
When he stood at Gainsborough, Quiet American was ridden daily or near-daily including some dressage work, according to the groom who showed me around. Not sure what is going on with QA since he moved to Darley at Jonabell.