Excellent point I hadn't considered.I could not find a catch either - I tried it last year here in Forsyth county. County came out and did a new valuation - it did NOT go down went up (I forget how much) but the tax increased like $700+.
Ownwell no help with that - got one letter from them after the new valuation, they still working on it - yea right.
I would recommend against it unless pretty dang sure value is down.