Brings back memories of singing that in high school chorus as a first soprano. Those are some VERY high notes!!
Yes, indeed.
Handel treated the human voice like any other instrument -- and expected singers to deal with the score accordingly. As a high tenor, after the glory of the ending, I've often felt as if I'd been garroted! That's why I sometimes "take breaks" by sitting in the orchestra as trumpeter...
But -- I still welcome any chance to sing/play Messiah -- one more time!
TXnMA