One just needs to wonder how & what sort of parameters were used to estimate the first superblock difficulty before it took off. Had I realized the shortfall of the superblocks timing I'd have warned Gatra but correction is still aplenty. It's just a matter of choice, etc.
The timing is based on block intervals, rather than a set time of day, so the exact time is not set, and will depend on mining power, difficulty adjustement and a bit of random, so day and time will drift over the course of months/years.
First super-block was at 19:50, latest was at 22:07, and we had one at 22:30, so it's not a huge drift, but it's a drift.
So chances are the dry spell will last a few weeks, until we drift to the next peak.
The peaks don't drfit. Suffice to said the current superblock made a poor navigator (more stationary than dynamic motion) towards the peaks as its reference. As casues of the blocks drift versus their standard timing were the factors stated then there should be some algorithm placed (perhaps a self correcting drift) to pinpoint the correct timing for superblock at the peak of hashing power.
Since superblock helded as weekly event some database peaks pattern (weekly updated for 1 month of data) built into miners would help guides the drift correction, etc.
Just a thought.