Anything you add/store in the camper in front of the trailer axles will increase the TW from published dry listing. Anything added behind the axles will decrease. Most TTs have more storage on or in front of the axles than behind, so TW typically goes up by 150-250 pounds based on what owners actually weigh.
Since TTs have high frontal and side profiles, they are more susceptible to changes in winds/airflow than most other types of trailers of same weight. Therefore, they tend to need the higher range of recommend TW, 13-15 percent to remain stable/comfortable to tow at 65mph.
Also keep in mind that 800 pounds of TW will add about 1100 pounds of weight to the rear axle and take off about 300 from the front, again decreasing stability. The WDH can restore those 300 pounds to the front axle while removing some from the rear axle.