There have been more than one block chain splits. I think you are talking about the hard fork that happened in May, which was planned for and not an unexpected accident. If you conduct a transaction and it is included in the shorter block chain, then by definition the network doesn't recognize the transaction and you keep your money and just send again.

I'm not sure what you're talking about, exactly none of the blockchain splits that have happened so far were expected to happen.

That hard fork was rolled out over a period of two months, with warning (whilst older clients were sent messages to upgrade) and smaller splits are part of the protocol and happen quite regularly. as expected (like when two miners hit the same block within seconds and they wait for the network to recognise the block).

That is the justification Satoshi Naakamoto gave in the original paper for waiting for 6 blocks for a full confirmation.