change data inside task

Dears,
i would like to highlight a bothering feature about task data management:

while you are inside task, if you have task duration <1 day, when you change data allocation every time you will lose also the duration that you set-up. and the new duration can be only >1 day


duration will follow mouse pointer, instead remanins still to 15 min previous set-up

I really don't understand what is the concept behind:

- chainging one parameter oblidge to change another one, not related one each other
- in PM i think is more common reschedule data without change duration than reschedule data while changing duration