I have been under the weather all week so forgive me if this post makes less than perfect sense. Experience has always been seen as one of those vital factors for Derby handicapping. When I look at the Derby I always view it through the eyes of 6 key factors. Speed, Fitness, Form, Class, Suitability and Experience.
Experience can be a tricky thing to quantify though. Horses with an apparent lack of experience (as defined by the total number of starts) are supposedly disadvantaged but no one really picks a horse because they the most career starts. The average odds of the Derby starters with the most career starts is 27/1 in the last 5 years. In fact if you take the three horses with the most career starts from every Derby since 2000 you get a cumulative Derby record of 24-0-0-3. Imperialism and Afleet Alex are only ones who managed to hit the frame.
Often an abundance of career starts is actually just a signal that the connections are not single minded in their intentions regarding the horse. They try turf, dirt, sprinting and routing all with mediocre results and then decide to have a flap at the Derby. Horses like Storm In May, It'sallinthechase and Supah Blitz are perfect examples of this and they are exactly why it is of no real advantage to have a plethora of starts.
Of course a horse does learn a great deal from their first few starts but there comes a point in every horses career when another start is just another start. It does not add anything significant in terms of experience and learning. That is why, despite the strong stats supporting it, I have chosen to disregard a minimum number of career starts as a significant Derby factor. Horses with less than 5 career starts prior to the Derby have a rather weak record of 20-0-0-3 but 5 is just an arbitrary number. Until this past decade they used to say you needed at least 6.
I think an extra start becomes irrelevant at the point when a horse would not be doing anything new. If your horse has had 4 lifetime starts but has never been out of allowance company or around two turns then obviously the horse needs an extra start in stakes company around two turns to be experienced enough. But if your horse was like Curlin and had already won a pair of two turn Derby preps he is not going to significantly aided by another start. He'd just be doing more of the same.
The raw number of starts matters less than what each horse gets out of those starts and it's different for each individual. Curlin was much further along after 3 starts than Street Sense was, despite the fact that they ended up being horses of very similar ability they learned at different speeds so how could one reliably state that "Horse A" could not be ready for a race like the Derby simply because of the number of times he has ran?
What is important in terms of experience I feel is that a horse face a largish field at least once and preferably not in maiden company. Sometimes maidens are full races but the best horse breaks on top and wins all by himself. In those cases it wouldn't have mattered if it were a field size of 20 or 3. Horses who did not face a field of 10 or more as a 3yo and also failed to face a field of 10 more than once as a 2yo are a paltry 34-0-3-3 in the Derby.
Another way I'd judge experience is by the types of races a horse has run in. The Derby is a brand new experience for all contestants but we've clearly seen in the past that a horse needs to have experience in a stakes route race. Horses who failed to run in at least one 9f prep race have gone 15-0-0-0 and horses who only managed to run one two turn race as a 3yo went 17-0-0-0. That seems to suggest that a bigger factor than total career starts is what kind of starts you had.
Experience is one key to winning the Derby but I rank it among the least important of the 6 keys to success. Speed and Form trump all the others and inexperienced horses will often beat experienced ones simply because they are vastly superior.
For this years Derby it means that horses like Big Brown and Denis of Cork will not be automatically tossed for the lack of total career starts. I'll watch their races and determine their experience based on how they actually do and what they get out of their starts.