The problem, is that you holding up all the other traffic for one pedestrians. Get the crossing length correct, have the elderly person cross at the start of the green then the time is sufficient.
Also changing the timing as one junction intermittently makes the coordination between set of traffic signals harder and can be big disbelief.
Notwithstanding, the wide junctions allow more space for cyclists.
<Disclaimer>: Dynniq sometime customer sand once-upon-a-time subcontractor </Disclaimer>