Just speculation - not sure HOW the protocol is established to handle this split brain scenario - what weird things might happen...
It happened to me too in the beginning. I think it's a good theory since the block time is fairly short with DIME it's possible there are block collisions or mini forks in the chain (split brain as you call it).
If you want to know what happens this is from the Bitcoin Wiki:
Blocks in shorter chains (or invalid chains) are not used for anything. When the bitcoin client switches to another, longer chain, all valid transactions of the blocks inside the shorter chain are re-added to the pool of queued transactions and will be included in another block. The reward for the blocks on the shorter chain will not be present in the longest chain, so they will be practically lost, which is why a network-enforced 100-block maturation time for generations exists.
These blocks on the shorter chains are often called "orphan" blocks. This is because the generation transactions do not have a parent block in the longest chain, so these generation transactions show up as orphan in the listtransactions RPC call. Several pools have misinterpreted these messages and started calling their blocks "orphans". In reality, these blocks have a parent block, and might even have children.
Because a block can only reference one previous block, it is impossible for two forked chains to merge.
..and: