I'm sorry to make a new post about this. However if I added this to the comments of the original post (which now as I am writing as 55 comments) I'm afraid people would miss it. As well I'll take the opportunity to mention another point for new members.
I'm a Talmid of R' Shammai Gross and have the zechus to m'shamesh him on a daily basis. Today I had asked him very pashut if that which dio should be "min hamuter..." is a din lichatchila, b'dieved, mitzvah min hamuvchar, etc. He responded that it's pashut that it's "m'ikar hadin". I asked what is the makor. To which he responded pashut that just like Klaf has to be, so to with this. Now I know there are those people here that will ask why I didn't push any further, for a better explanation, etc. however it wasn't the right time (for a few reasons) and that he was clear in the psak. He of course mentioned the discussion of using Stam yanem, but for sure has to be from a "min hamuter..."
Any shailos that appear here without anyone asking I usually ask to R' Shammai anyway and post his teshuvas. If there are any particular shailos that one would want to davka be asked please feel free to post them here or to send them privately to firstname.lastname@example.org
(I don't always get to everything and depends on the day, what other shailos there are, etc. but will try my best.)