This proposal is not aimed at addressing any known vulnerability, contrary to what some might suggest. It's important to understand that blocks with valid transactions inherently do not suffer from malleable block hashes, indicating that the issue this proposal aims to tackle might not be as critical as presented.

Moreover, the method suggested for mitigating what is known as the invalid block hash caching weakness introduces unnecessary complexity and incurs higher costs compared to existing solutions. The argument against the utility of caching invalid messages as a means to optimize against Denial of Service (DoS) attacks is substantial, highlighting that such practices may, in reality, be counterproductive.

From a consensus perspective, implementing a rule to invalidate these transactions seems redundant and likely to introduce more problems than it solves. It demands additional validation checks that are not essential to the system's operation, thereby complicating the process without clear benefits. Although there might be a case for considering this move as an optimization technique for Simplified Payment Verification (SPV) bandwidth, it's crucial to steer clear of misrepresenting the measure as a remedy for a flaw within the system.