Thanks for contacting and giving your feedback.
In answer to your question, whether story estimates are driven by task estimate roll-ups, the answer is different, and it changes based on the team preference, maturity and methodology they use.
Currently TeamPulse let teams use different metrics for planning and estimate of story - like points, and hours - for planning and tracking task. As those values not necessary are in same metrics, the roll ups might not work as expected.
What we plan to implement is to have to values for the Story item. One to be the initial estimate base on the units you use and the other to be Story task estimate – the second one will be a roll up from all the tasks related to that story. This way, both values will be visible and be an object of future analysis and comparison.
Will this feature be valuable for you?
Thanks a lot,