Respectfully disagree. As mentioned I've had misconnects at HKG that simply would not have happened at SQ. Central screening involves walks to central points, you can literally walk 5 mins queue for 20 mins and walk 5 mins to be back at the gate next the plane you've disembarked. you come from. At SIN, you're there as soon as you get off the plane, so if you only have 20 mins because your inbound is late, you should not misconnect. In most central security situations you would.
Also, in theory you could put a lot of staff at central security points, but you get an influx of flights all at once for whatever reason that security point could well back up despite best laid plans.
And I don't think everyone is comparing to the US, I have plenty of examples of long waits at central security at a diverse range of airports - from LHR to HKG, to NRT to BKK to DEL. When I connected through DPS a few weeks ago, it worked well though with a central security point, but it's not really that much of a hub for I-I connections.
But we're never going to agree on this.