2.x RTC Planning features in 4.x
Accepted answer
Yes this feature is still available. Please the the following article on Jazz.net. Scroll down to the Validiate a Plan section of the article.
To assess individual work items, add the Completion Probability, Maximal Estimate and Minimal Estimate columns to plan views and optionally to your execution work items (e.g. tasks). Once the Completion Probability field is added to your view this will run a simulation and color work items according to the calculated probability of completion: a color gradient from white to red indicates very probable to won't happen.
You need to enter Maximal Estimates and Minimal Estimates in addition to the Effective Estimate field in order for RTC to run its simulation (monte carlo)
The following aspects are considered when the completion probability is computed: Effective Estimate, Minimal Estimate, Maximum Estimate, and Schedule Sequence (after what items is this item planned). For stories with children, the worst child-probability is taken.