Shtikoh Yofoh B'Sha-as HaTefilloh!

According to Minhag FFDM, the Gabbai or the Shatz announces "Sh'tikoh Yofo B'Sha-as HaTefilloh!", before Boruch Sh'Omar. I believe there are other instances where this is announced but not necessarily specific to Tefilloh (it might be before Tekias Shoufar amongst others). When are those times?

Rallis

R' Shimon Schwab comments on this minhog (in the book Rav Schwab on Prayer, p. 120):

'There is a uniquely "Frankfurt" Minhag for the chazzan to announce, before beginning Baruch Sheomar: ...Shtikoh Yofoh B'Sha-as HaTefilloh - It is a beautiful thing to maintain silence during the Teffilah. However, this is an inaccurate portrayal of the actual Halacha. It is not only "beautiful" to maintain silence during the Teffilah, but rather, it is absolutely forbidden to talk during the tefillah, from the beginning of Baruch Sheomar, until after the end of Chazoras Hashatz...However, what this announcement does mean, is that we are asking our neighbors in shul, who may not yet have reached Boruch Sheomar, to please refrain from talking - and disturbing us - so that we may concentrate on our Tefillah. This is the meaning of yafa. It is, indeed, "beautiful" and considerate of others to heed this request.'

Daniel