There are several issues with the hand replay viewer. I think they’ve been discussed in other threads and I guess the staff hasn’t deemed it a priority, possibly because it would take a lot of work.
Often I want to review a hand and don’t want to sit through the entire real time replay. Without the ability to fast forward or skip it’s very tedious.
As an alternative proposal for a simpler solution I would suggest making a text based summary of the hand action available on the hand replay page. This would allow someone to quickly review the hand and should be easy to implement.