Thanks for the link.

I see two issues here. First there is the very small miner reward that has already caused the difficulty to fall drastically and then there is the delay in the difficulty adjustment that is causing the very slow blocks. The latter phenomenon is seen in other SHA 256 coins, for example Freicoin, where a sudden drop in hashrate is not reflected in a corresponding drop in difficulty. This can cause the hashrate to fall even further in a vicious circle and lead to very slow blocks. Freicoin is a good example because it has a tail emission from the demurrage. This shows that the slow blocks are not caused by a lack of a tail emission or very low emission alone, although a very small emission can aggravate the problem. The slow blocks are for the most due to the recycling of old ASIC Bitcoin miners to mining other SHA-256 coins. This can lead to sudden drops hashrate that cause the slow blocks because of the delay in difficulty adjustment. I do not see this been an issue with Bitcoin since Bitcoin is by far the lead SHA256 coin. The very small block reward in Ixcoin on the other hand is a warning of what can happen to Bitcoin security wise.