How long is too long for sous vide steak I have sous vide for a while with mixed success. Mostly good, but still mixed.  One thing I question which I hoping to get opinion on is time to sous vide beef (steak specifically, e.g. ribeye or strip).  

I have read and heard where people have left beef in the bath for 24+ hours and rave about it. All the Anovo guidelines say 4 hours or less. I have not tried more than four hours.  What gives, and what is overdoing it with sous vide cooking?
When cooking low temperature, over time the texture of the protein that you are cooking changes.  For a tough cut, like a shank, or short rib, this is desirable, and where you would see cooking times of 12, 24, 48 hours...or longer.  Most people want to enjoy a steak that chews like the traditionally cooked product.  After 3 to 4 hours, the texture of your steak will change.  It will become more mushy.  That is why it is recommended that you only cook until done (1 to 2 hours).  So, overdoing it, as you describe it, would be cooking it too long so that the texture becomes undesirable. For a steak, I think 4 hours would be pushing it.