According to this answer R' Moshe Feinstein Paskened that, since for many years the practice of Bentching on a Kos (reciting grace after meals over a cup of wine, as formally constructed in the ...
For one whose custom is to drink wine (or grape juice) after reciting Birkat Ha-Mazon and to refrain from eating wine during shavua she-chal bo Tisha b'Av: Does the requirement to use a cup trump the ...
After saying Birkat HaMazon with a cup of wine, the Shulchan Aruch rules in OC 190:3, that at least a cheekful of wine must be drunk. If this was at a zimmun and the leader of the zimmun does not want ...
Bentching with a kos (recite Grace after Meals with a cup of wine) was clearly a popular thing to do in the times of the gemara. Additionally many Ashkenazi rishonim (Rosh, Ri, and many other ...