Not really, it'll force the model to fly in a very near neutral pitch stability point but this is how F3A models have been set up for decades and is the best way to do it. Any desired SMALL amount of pitch stability can then be trimmed in using a smidgeon of up trim and a small shift of the CG to a point marginally forward of the aircraft's neutral point. Granted this isn't the way that normal sport models and especially trainers should be set up but it's entirely normal for aerobatic models. In many cases the modern 3D models are actually purposely set up with the CG BEHIND the neutral point and the stability issues are tolerated to gain more ability with the post stalled 3D maneuvers. It makes for a busy workload if you're flying "normally" but if done within reason it's tolerable.

Gaiotto, the anhedral in the stabilizer on the Curare was not put in there just for looks. Shifting the stabilizer like this has been done on other models and in the articles explaining why it was always done for a reason that was often related to knife edge performance or some other aspect where a correction was required. The builder choosing to put in anhedral as a "repair" rather than rebuild the whole fuselage So if you WANT to use anhedral then you should really be looking at where the optimum point for the vertical center of the stabilizer should be and then shifting the root mount point up so that the effective vertical location is correct.

I'm not an F3A flyer myself but I've seen references to other pattern flying issues where these days it's more common to just build the model to the best design parameters that are known and then if there's any minor issues with knife edge or vertical lines or whatever then you use the programming mixes to fine tune rather than cutting into the model to add anhedral or other fixes.