I agree, totally wouldn't worry about washing this year, especially i it is only a 2nd generation. There are theories out there to why you should not just pitch the entire cake, but on a practical level my experience is you just won't notice a difference. Now, if you were picthing the entire yeast cake on a low gravity beer you might. And you certainly will start having problems after multiple generations, but on a fresh, single gen picth you will absolutely be fine.