Clearing Harbourfront has never been a problem at all even though the place is small. Anyway the traffic is always controlled by the scheduled arrival and departure of vessels - so situation is not that bad. Knowing the civil service gungho mentality, they will form a task force to look into every problem.
My original post was about the situation was when Mas was still loose.
Currently if you are a Sporean entering through the Harborfront immigration is not a problem because 50% of the counters(manual & auto) are reserved for Sporeans/PR.
If you check my previous posting. last paragraph, I noted thise:
"At harbourfront the delays are worse because there are fewer counters & the checks more rigorous. Not for Sporeans but for foreigners."