I have a question complementing this thread.
I have copied a chunk from the whitepaper:
The average work required is exponential in the number
of zero bits required and can be verified by executing a single hash.
For our timestamp network, we implement the proof-of-work by incrementing a nonce in the
block until a value is found that gives the block's hash the required zero bits
Every 2 weeks difficulty is adjusted to keep the 10 minutes avarage in place, but how can this be garanteed since adding or subtracting a nonce will change the difficulty and thus the average exponentialy.
Is there no risk the average will go from lets say 8 minutes to 16 minutes ?