I had a conversation with an athlete recently in which he declared he was "going sub10" at his Ironman "A" race.
This could create a sticky situation for a coach because you want to be encouraging but at the same time, you also want to have the athlete's feet grounded in reality.
When an athlete makes a declaration such as this to me, I like to go through the results of that particular race and see what that goal looks like in reality.
Having just broken the sub10 barrier myself, let's pull up the results from Ironman CdA as if we were going through that exercise with me.
When I look at the times, I see that in order to go sub10 at Ironman CdA, I need a 1:0X swim, a 5:0X to 5:2X bike, and a 3:1X to 3:3X run.
While there are definitely outliers (folks with a competitive past in one of the three disciplines), if your not hitting these ranges in your individual training sessions, your goal might be something to work on over several seasons. (It was for me!)
For Ironman CdA, my splits were as follows:
01:03:34 Swim
00:04:18 T1
05:20:41 Bike
00:01:02 T2
03:24:38 Run
09:54:13 Total
As you can see, I fall within the ranges listed above.
I know, it's fairly unscientific but it's a quick test to see if your goals match reality. In my case, they did.