That's a no-go for me. The 49% of non-malicious miners would be ruined afterwards and discourage others from following similar pursuits. Changing the hashing algorithm may not be beneficial either since we'd have to rely on cpu mining, which would make it a lot easier for a malicious party with resources to attack. The way things are structured now, the acquisition of asics will impose a new cost on attackers which trumps the marginal cost of allocating existing computing resources.