example: Ian Jory

overall ROI: $1.42 in 1095 starts. this guy performs a bit below the market, but probably no way to make money looking at this stat.

routes ROI: $1.13 in 535 starts. his horses don't do so well going long. in my opinion, this stat can be useful, as his ROI has a noticable drop in this category.

sprint to route ROI: $0.90 in 122 starts. again, I think this stat is useful, as it proves that he can crank em up sprinting, but may not train as much stamina into his horses as other trainers.

last race 11-29 days ROI: $0.94 in 614 starts.

last race 30-89 days ROI: $1.45 in 268 starts. these last two stats are somewhat useful. most horses run slower on short rest, but Jory's run even worse than the market thinks they will. in the 30-89 day category, his ROI is in line with his overall ROI.

4-1 or less ROI: $1.39 in 208 starts
over 4-1 to 10-1 ROI: $1.88 in 312 starts
over 10-1 ROI: $1.17 in 575 starts

I think these last three stats are somewhat uesful. when Jory's horses aren't taking any money, they perform below the market. of course, most horses who don't take money don't run well. in Jory's case, however, they perform even worse than expected.

STK ROI: $0.70 in 111 starts
a useful stat I guess. his horses underperform when running in stake races.

out of the 27 stats that TG provides on Ian Jory, 15 or so do not mean that much to me, as the samples are too small. of the stats that do have some importance to me, I do not think any of them looked at alone will make anybody rich at the race track. I do think, however, that if you get a general idea of the strengths and weaknesses of each trainer, you have a leg up on your handicapping competition. Ian Jory's horses look to be a bit stronger in sprints than in routes, and his horses tend to get overbet in stakes races. sure, Jory's next three sprinters may lose, while his next three routers may win, but in the long run, you will have more success betting his sprinters.
in my opinion, if you can get this sort of general feeling about every trainer, you do have a handicapping edge.