TPA sillyness

Somebody explain this one to me. DXR (Danburry, CT) lists:

Pattern altitude: 1701 ft. MSL
TPA FOR JET ACFT 1743 AGL

The field elevation is 458. I'm cool with the higher than normal TPA
(there's some big hills right next to the airport), but I don't
understand where they got the strange numbers from. What bit of
regulatory sillyness makes them publish a TPA of 1701 instead of 1700?
I've always flown it at 1700; I guess I should file a NASA report for
busting the TPA all these years?

And what is the advantage of having the jets flying 42 feet higher?