multi coin solo mining I'm wondering about switching coins while solo mining? 

Does switching before I block is mined effect the odds of getting a block reward, or is it always essentially chance??
For example, if I mine for 30 minutes on Feathercoin, then jump to Litecoin, when I come back to Feathercoin will there be any accumulated value in the wallet?

Am I ever starting over, or is it always chance?

By the way, I'm using a node stratum pool, so it's direct connect to the wallet.
Every single attempt at mining a block is independent of every other attempt and has precisely the same chance of succeeding. There is no intermediate work to save or lose.