So during the bcash fork, the suggestion was to send all coins that were in your Electrum wallet to another wallet under your control (after the fork), then it would be safe to send your old wallets seed to a bcash wallet for bcash coin extraction.

I am guessing that can't be done here for s2x, because if you did, your old pre-fork wallet is now empty of both bitcoin and s2x coins, (as coins have been sent to the new wallet after the s2x fork), the private keys of the old wallet won't contain either bitcoin or s2x coins. As for the coins that were sent to the new wallet (under your control, post-fork), well nothing has changed for these coins, so if you sent them to anyone else other than yourself (in another transaction, eventually), they are still vulnerable to replay and loss of the other chains coins (the coins on the chain you meant to send are still safe as always). Can anyone verify this statement is correct?