Can I save mining fees when doing transitive transactions? If I create two transactions:


Send BTC from output X to Y, no fee is attached.
Send BTC from output Y to Z, fee is attached (this depends on the previous tx).


Would nodes propegate these two transactions? Would miners mine them?

In other words, if transaction T2 depends on T1 and I want to broadcast both together - can I save some fees on T1?
Probably not. Clients can set whatever rule they like for transaction fees, but they normally adhere to the Satoshi client rules described at https://en.bitcoin.it/wiki/Transaction_fees. However, note the section on transaction priority; if you have an address holding some old coins, it's quite likely a transaction out of that address will have high enough priority for you to avoid transaction fees by default.

To implement what you describe, you would need a client that does something like hold all low-fee transactions in a small pool and watches for new transactions out of their output addresses. That's certainly possible to implement, but it seems to me that it would be the sort of service you'd pay a premium for, not receive a discount on.