a) I guess taht would answer tosfos’ kasha on Rashi for me, unless tosfos doesn’t hold that lach b’lach is meurav. Why would we say that its mevashel kdei klippah by bassar b’chalav if its lach b’lach? Maybe there’s something there that tosfos holds applies by me too. (Sorry if this is beyond the scope of what you are doing- I’m not sure if you’re only learning aliba d’hilchisa if you know the sevaros and pilpul behind everything- but if you do I appreciate it- I have to give a chabura on wednesday!)
b)Yeah we are doing bishul or at least working our way through perek kira right now. We just started the sugya of kli rishon kli shayni but I’m not sure how deep we are going to get since the zman is almost over and we’re supposed to start rechitza on wednesday.