Yep because cleaning of cubes/FVs is different than cleaning something with a known infection. We all know nothing is sterile in homebrewing and thus normal cleaning of something which has not had an infection should be thorough, but it is essentially already sanitary as many find out from pitching on top of a yeast cake.
When you get a bad batch, you know there's something unwanted in there and therefore need to be sure it's gone.
I'm happy to make this a kinda test through first just following a regular PBW soak, water boil, starsan, wort boil (I realise the starsan step may be redundant/pointless here? thoughts?). I'll taste my starter and see if it is sour like the last one (which I attributed to the leftover wort I used... silly me), and also will only use LDME to make the wort so it has 'neautral' taste/aroma and should make it easier to detect if the nasties survived.
