Mr-AEO,
The driver for SRVLs is not deck erosion. Deck erosion is an issue, but it's not the reason SRVLs are being looked at. The real reason is the UK desire to get back to the deck carrying more at higher temperatures.
Don't think I ever said that SRVLs will be as safe as a purely VL. I don't know what the relative safety analyses say. Al I do know is that the team will not recommend SRVLs unless they can be made sufficiently safe. Oil on the deck -yes, absolutely a problem. That's why the USN take severe pains to get rid of them ASAP. They are a problem for CVN arrested landings as well.
Best Regards as ever
Engines