I always string gut as 2 piece, as there is less handeling of string.
Also keep in mind, as no matter what racquet that you are using, even though it may be okay for your racquet to be strung bottom up with the pattern of your racquet, the crosses, I always string gut 2 pieces and the crosses from top to bottom, as most of the hitting is at the center to top, and you want that gut to be the best condition at the top, as the gut gets handeled more as you work crosses down to bottom, so the last few crosses on the bottom are handeled the most rather than on the top, if you follow that.
Also if you tie a good knot and up the tension of the tie offs a percent, there should be no difference in tension maintaince between a 1 or 2 piece.The only difference is the additional tie offs between a 2 piece and 1 piece, and if the tie offs are not handeled properly, then I can see the tie off strings being looser and eventually effecting the long term tension maintance of the stringbed, but if handeled properly there is no difference.
Also with all nat. gut , that string holds its tension better than any other string on the market!