In comparison to last year's edition this edition has some downgrades on realistic behaviour that annoys the human playerer alot.
In mountain stages, the peleton ( even on extreme ) has the mentality to way to hard in the beginning of the last mountain. If you put your riders on an tempo ( dot ) that is more realistic and knowing it can last till the end, a large group will be in front of you until like 4-5km from the finish, where 3/4 of the peleton has no energy left.
Your rider still has energy left and starts to catch all the riders, but is hindered and halted from all the slow riders, making it impossible to get back to the front of the peleton. That way you get in the last2km with enough energy but a huge gap till the front favourites that you can't close.
Simular is on sprints ( and surely in break-ways ). If you are in a breakaway and continue to the finish. The entire group starts sprinting from way to far ( like 2.5kms ). Then if you start sprinting on the right timing, you can't win, because 6-10 riders are sprinting next to eachother without red bar left, and you are behind them with no option to overtake.
So both these examples are a method of the AI screwing up, but the human player gets screwed more. It seems that PCM 2017 is alot worse then 2016 in terms of moving up or catching slower riders. You get haltered alot more.
The sprint train is another option that has alot of problems on the mountain stages. Other riders can ride between your train creating gaps, making the last riders lose more energy closing the gaps, then the front guys of the train ( and those are weaker riders).
On hilly stages with alot of ups and downs, this can even create gaps, where your train is in different groups ( Peleton, A1, A2 ) what is really quite impossible. you make a train in the begin of the hill, and on the top, they are'nt even in the same group anymore. While the last riders are the strongest...