Since 1.4 I've probably saved at "P" depth ( or greater depth ) with and without a crowd of DD's breathing down my neck at least 30 times and have yet to have a corrupted save. Course I run a stock game ( except a few texture mods ) so I can not vouch for any mod screwing up. 1.3 and before was a different story.
Although this pic was intended for a compass mod there were two enemy DD's and a light cruiser looking for me less than 2500 yards away and I saved three times under surface and never had a problem.
Computers are computers and people are people which are a lot different. So who knows what really goes on in SH4 world ? Mine doesn't crash ( or corrupt under surface ) the next guy's does.
OK back to that save.
Note to self: Must refrain from hijacking threads.