[Mesorah] S. Baer on Shelo Assani Nochri

[R. Rich Wolpoe]

Caveat: I'm not taking a stand on whether or not adding "lanu" to Birkas Eirusin is problematic. But IF it is, then I would think that adding piyutim to Birchos Krias Shma and to the Amidah is even *more* problematic. »

It's kinda apples and oranges
The Nusach of birkas erussin is in the G'mara and RT AFAIK didn't change the girsa in the G'mara. He just saw the text as ambiguous and misleading

And Baer felt the same re: Goy.  It seems a good zu-shtell LFAD.

That doesn't necessarily mean one MUST change.  I'm just saying it's quite a legitimate change 

As to your question re: Piyyutim see Hirsch's Shemesh Marpei #2 on the subject.
Shalom and Regards, RRW