Crisis averted! Eastoak- you're right I didn't give it enough time. And, as stated by Helibrewer, the fermentation did not appear identical. However, both starters turned out just fine. Potentially the 3056 was dominant in one and S33 the other. Either way, both 5 gal batches are doing just fine. Just to be sure, I sampled some the other day and it was great; No off smells, odors or taste. So, chalk this one up to paranoia/impatients.
I have been brewing for 4 years no and have never had a problem with cross contamination or infection... until the last batch of porter. I am new to kegging and had recently kegged a hard apple cider that I had made w/ champagne yeast. Well, i made the rookie mistake of not sanitizing the out-going hoses which is why I ended up with Porter/wine. I have since started soaking the kegs in chlorine bleach for at least a day and running the bleach through the lines but this has done little to ease residual anxiety.
Re: bleach not being the best as a disinfectant- I disagree. Bleach is widely used in both the medical world and the food industry to kill all manner of beasties. Additionally, the military uses it during decontamination operations because it is extremely effective and cheap. Not to say that I don't use star-san. In fact, that is what I'd used on the champagne-yeast-contaminated-kegs. As long as it is mixed in correct proportions (at least 200ppm) and has adequate contact time, unscented household bleach is a cheap and effective sanitizing agent.
I know it can be hard to judge tone via blog but here is a non-snarky question. Why wouldn't I make a yeast starter rather than double pitching? Did not the Godfather of Brewing (Papazian) recommend it? I make a starter every brew (except for the last Porter/Champagne) in order to ensure that my yeast is the dominant culture present in my brew. 100 billion cells supposedly exist in a packet of 3056 (barring degradation of viability over time). 100 billion cells pitched into a 2 liter starter will only grow to a bit over 200 billion cells (growth rate of 2.05), while the same 100 billion cells in a 4 liter (.5 gallon/ 1 growler) starter will grow to about 400 billion cells (i know growth is exponential to a degree). More than enough for a 5 gal batch at 1.075. For example, 5 gallons of ale at 1.048 gravity needs about 177 billion yeast cells. So, a 100 billion cell packet pitched into a starter of just over a liter would be sufficient for that beer. Add another packet of dry yeast on top of that and you have way more than enough. I always do growler sized yeast starters b/c, all things equal, it is enough yeast cells for a 1.085 OG brew. I sincerely thought this is a "best practice". If for nothing else because it affords me the opportunity to panic when viewing the starters the day before the brew. Other than exposing the yeast/starter to contaminantswhy wouldnt i use a starter rather than double pitching? Sure I have to buy an extra pount of DME.... but it gets added back to the beer anyway so I'm not really out anything.
Thoughts?