question - in this block chain I've observed that block are not being generated at the advertised rate.
There is no such thing as an "advertised rate".
Block: 42105,Target: 69.91 GH/s, Hashrate: 9.81, 9.30, 9.27 GH/s, Performance: 20.41%
Diff: 1953.27040885, next: ~488 (confidence 47%) - Last Retarget: 56.33 hrs ago, change in 375 blocks (~61.25 hrs)
Expect to see blocks on average every 10 minutes for now, until either difficulty changes in 2-3 days, or hashrate increases back up to the target.
so this in the OP in not true?
Coin Specs
Algorithm: Scrypt
Block Reward: 20 BTM (visual)
Block Time: 120 Seconds
Block Maturity: 720 Blocks (~1 day) to discourage multipools
Block Halving: Reward halves every 3 years, with intermediate decrease every 18 months (20 coins initially, 15 after 1.5 years, 10 after 3 years, etc...)
Difficulty Retargeting: 720 Blocks (~1 day)
Total Coin Supply: ~27.58 million (27,579,894.73108000 exactly)