Hello,
how is ensured that secret and new commitment transaction exchange take place at the same time? If for example Alice sends Bob the new commitment transaction only if he sends her a secret for penalization transaction activation, and she lies, it can end by balance freeze forever, because at now Alice has secret and Bob has nothing, so Bob can't send a transaction to blockchain (if he does it, Alice uses his secret to take all his money from the channel) and Alice does not do it because she wants Bob broke even if her money are freezed too.