I am looking for validation (or invalidation) of my assumption of what strictly counts as a fork in Ethereum.
If you start filters to multiple ETH nodes at the same time, you will very often see 2 or more blocks mined at the same height.
My understanding is that these off chain blocks will always be included as uncles in future blocks, with the following two cases counting as a fork:
1) a child is mined with an uncle as its parent (i.e. the classic type of fork you would see in BTC)
2) A reorg, e.g. a block that was regarded as main chain is swapped with an uncle block at the same height.
Can anyone tell me whether this is accurate, is it missing anything, and are there any errors in the above assumptions?