Is G_txcreate added once and not if a contract creates another contract?

[siladu]

https://github.com/ethereum/yellowpaper/blob/f41ec9a6785374c1d9b9e9a064e3ceae1413805a/Paper.tex#L704

$G_{\mathrm{txcreate}}$ is added if the transaction is contract-creating, but not if a result of EVM-code.

[siladu]

Answer from @ajsutton:

A contract creation within a contract is not included as intrinsic cost but may still pay for it via the opcode.