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I sincerely welcome and I'm very grateful for any research provided that is contradictory to my methods. My goal is always in the interest of best practice.
[...] My method has very little risk. I am pulling from the master to make 10 or so little 4ml vials filled halfway with yeast and the rest with a water/glycerin solution that's been sanatized by means of pressure cooking. The rest of the pouch (or vial) is then put into a 1-liter starter on a stir plate to be pitched in a batch. The vials are then prepared and labeled for storage in an isulated box in the freezer, so that later each one can be made into a starter for another batch of beer. Each contain a fresh culture which isn't susceptible to mutation, but bacterial infection could happen if I messed up.
The only risk I see, other than the starter, is dividing the package of yeast which is done in sterile conditions. For this step alone, I use a near-sealed clear Tupperware with gloves mounted to the side and work inside this box with the lid on. The container is drenched with a disinfectant/sanitizer and left to sit for a day with Seran wrap around the lid. Many brewers do this just fine without these extra safeties that I use. I would just hate to give someone a strain that's not absolutely pure. The way I do it, I can be positive that it's clean.
Here's the tupperware "busy room."

and here's the inside.

Notice that all holes were filled with silicone and there's a rubber/foam gasket glued around the rim to seal the top. I also clamp this in place on all four corners when it's being used. I intend to put a plexiglass window in the top but I haven't found a cheap supplier of 1'x8" plexiglass and I don't have an appropriate tool to cut a larger piece down to size.
It's almost necessary to make a starter anyway if the batch is above 1.060SG or the vial's "best by" date is less than a month and a half away. Making it from a 4ml vial instead of a package of yeast is only one extra step-up. Someone could buy two vials per batch but I can't really afford that. Using this method I can start a high gravity beer for around a dollar and if the starter gets infected in the process, it costs me much less to try again. That's also the beauty of a starter; It's like an acid test for your yeast at less risk than pitching the vial.
To avoid infections, I'll always wait until I drink the finished beer before using it's daughter vials. In order to prevent mutations I'll never wash yeast from a high alcohol beer and never wash the same yeast more than four times. (White labs suggests no more than 8-10, but the other experts suggest 4 or no more than 6.) I can just make 10 vials from each package of yeast, and repeat that four times in a row on each subsequent vial with enough left over to pitch. One package could potentially yield 10,065 batches of beer without the need to use washed yeast. If one batch is infected, I could simply destroy any of it's siblings and start from a different lineage. The first starter will tell me if the parent vial was infected before I made children vials. And if the resulting beer was bad, I would know before using or sharing it's children vials and destroy them before propagating them. Of course I would make atomic-explosion sounds and laugh maniacally while I did this.

But the chance of mutation is along the order of one in half of a trillion or so cells as long as they are used with lower gravity beers and their temperatures are moderated well enough. Also mutations tend to not reproduce well. Homebrewers typically only work in the billions. So if I treat my little yeasties with dignity and respect, they'll love me long time.
And I would say that overall, it's not very difficult. I took health and safety courses for tattooing and yeast washing is cake compared to that sanitation procedure, and it's WAY easier than growing certain "kinds" of mushrooms, too, which takes crazy-ass sanitation.
I just finished making this from a single 4ml vial, and it smells, tastes, and looks perfect. 8-)

This is a 2-liter flask and it has way too much yeast for this batch (probably 5 white labs vials worth) but that's credited to the benefit of the stir plate. Half of this flask is what I need, the other half is to be stored or given away. I think it's super geeky but easier than it sounds. I would say that if someone can make an uninfected batch of beer in a bucket, they could ranch yeast. Just remember to always make a starter, and closely watch, smell, and taste it, which many brewers do anyway.
Good Luck!
