Training Feat?
 

Has this ever been done before over such a large sample:

trainer Tony Richey who trains at Delta Downs has a record of 37 wins in 79 starts. That is almost a win one and lose one record. I know guys have gone on runs before, but just shy of 50% over 79 races?

That's pretty stout considering they've been running since October. Usually the only time I've see it is when they have a nice string early in the meet, their number blows up, then gradually declines over the balance of the meet. For instance,

Anthony Pecoraro is clipping off 41% through the first 8 weeks of the Tampa meet - 12 wins in 29 stars.
His brother Matteo is checking in at 42%, though a smaller sample - 5 wins in 12 starts.

You can't leave either off a ticket. Right now. But by the end of April, I'd be willing to take odds that they're both back down to the low - mid 20's in percentage won.