No. Max weight is max weight. If your truck manufacturer says max tongue weight is "X", then that is the most they recommend. Here's the straight story based on my recent experiences (2016 Nissan Titan XD SL diesel and Grand Design Reflections 313RLTS):
1. I must not exceed the GVWR of the Nissan (8,800 lbs as specified by Nissan), whether towing something or not. I drive on to a CAT scale - in any configuration - and I must not exceed 8,800 lbs, AND
2. I must not exceed the GVWR of the 313RLTS (10,995 lbs as specified by Grand Design), AND
3. I must not exceed the Maximum Gross Combined Weight Rating of the Nissan (19,450 lbs as specified by Nissan), AND
4. I must not exceed the Maximum towing capacity Tongue of the Nissan (1,231 lbs as specified by Nissan using a WD hitch), AND
5. I must not exceed the Maximum towing capacity (12,314 lbs as specified by Nissan).
These are all the sticker numbers on your truck and trailer. They will vary by manufacturer, but the bottom line is that you must meet all five of these criteria if you want to "play by the numbers".
That is not to say that your truck cannot exceed these numbers safely; it just means that these are the numbers that the manufacturers are living by.
Thanks.