what is a Good Training Speed?

[Narf]

First of all - it doesn't matter if a player has participated in the match or not, all the trainings have a specific number of condition to spare and skill to gain. You can see those numbers when you hover the "buttons" for each of the 3 types of training (10% is indeed the standard for stretching).
What should be considered "good" is subjective, but generally if they gain more skill than the standard number - it's good. If you're talking about the often mentioned "fast trainers" however, then you're looking for at least 50% more skill gain.

[RSoul]

First of all - it doesn't matter if a player has participated in the match or not, all the trainings have a specific number of condition to spare and skill to gain.

I was under the impression that if they had played that day they would gain more from Training after that match? Do they gain more depending on how much current condition they have? e.g. it would be better to train when at 80+ condition when it its bright green rather than below 80 when it is a light green color

[Narf]

I was under the impression that if they had played that day they would gain more from Training after that match? Do they gain more depending on how much current condition they have? e.g. it would be better to train when at 80+ condition when it its bright green rather than below 80 when it is a light green color

No, the skill gained will always be the same per player, regardless of whatever factors you could think of.