FrozenThaw: Mentioned somewhat earlier about davening quickly/slowly this might have changed. Because it is well known the Belser rebbe zy”a said to daven quickly so no disturbing thoughts should have time to interrupt your kavana. On the other hand, it is also known that Brisk pronounce words slowly to be mdayek.
mw13: “Hachama niskasa m’eyneinu” must be the zman because Tzais is Tzais and not Shkiya. How long does it take from Shkiya till tzais? for that you have many answers. Also, dividing the world in different places to calcullate. Just like time zones can change. How do you calculate when it is cloudy and you cannot see any stars?
In Yerushalaim Chabad has a minyan maaariv mtzsh”k 25 min after shkiya, also 60, also 72. The debretziner paskened in NY it is 56. But of course you have to know where you live. Go to Gateshead or Alaska and in the summer some hold 72 even there. Is it Ameratsus or Shitah? (no difference, just stating)
DY: If you have such a question you should ask you rabbi. If you are a Rabbi, don’t pasken based on internet info.
Those yeshivish Talmidei Chachamim who don’t eat Chssidish Shchitah choose not to do so but will not take b’chirah away from you since it is not treif just a hiddur. And hiddur you are not allowed to be machbid on the tzibur. If you don’t want to eat Satmar you don’t have to. There are many options. There is no reason to come out against them. Since a learner would know ” Asse L’choh Rav”. everyone asks their rav .
Klal Yisroel started with 12 Shvatim, Each had their own Nasi. and they did pasken differently and none was Neged halacha.