As long as you're not travelling with the crowds, you 'should' be fine.
Which is to say, get there well in advance and leave before; or well after everyone else does to head home.
During any holiday time traffic can be very heavy, especially when:
1. There is an accident. (often)
2. People are stopping at the side of the road to buy something from vendors. (often)
I've seen a couple times where the traffic has been backed up to 7 kms (~4.5 miles). (not so often, but it has happened)
It becomes doubly dangerous at these times, because most people want to pass and there's not many safe opportunities to do so.
People do it anyways, such as passing while going up a steep incline on a corner.
There are lots of pinch-points along the route where bottlenecks can occur.
If you do go, be safe and enjoy!
