If you add 9 known not-very-good sources of randomness, it's still better than adding no sources of randomness. Now if your 9 bad sources are 100% predictable,

If you add 9 known not-very-good sources of randomness, it's still better than adding no sources of randomness. Now if your 9 bad sources are 100% predictable, then yes, there's no point in adding them.