5-7% tongue weight is not enough.
GM recommends 10-15% as does my own truck owners manual. I would rather believe the auto manufacturers then some freelance Basspro writer. That said, there are a lot variables involved, but I would never tow any trailer - boat, utility, RV without a minimum of 10% tongue weight. If you have ever seen a trailer swaying or porpoising (many examples on YouTube), that is an easy way to tell that that weight distribution is way off and or the tow vehicle is not rated for the weight it is attempting to tow.
Also in general, don't anyone be mislead about the advertisements that xx vehicle is rated to tow xxxxx lbs. A good example would be a 1/2 ton pickup that is advertised to pull 10,000 lbs. Most of these trucks will run out of payload capacity and GVWR long before they hit that advertised rated tow rating. What those advertisements don't tell you is that every vehicle has a different true tow rating and GVWR.
To achieve these advertisement numbers, the manufacturers use carefully stripped down vehicle models that are barren of any options, no floor mats, no passengers, minimal fuel, no spare tire etc. Also the trailers they use for testing are not boat or RV trailers and are usually long, low, double axle and the weights they use are carefully positioned on the trailer.
I always tell people to check that yellow and white sticker for their truck - usually on the drivers side door jam. It will list the GVWR and also state to the effect:
The total weight of people and cargo should not exceed xxxx lbs. My owners manual says: The GVWR is the total permissible weight of your vehicle. including driver, passengers, vehicle, options and cargo.
Best is to go to the scale with a full tank of gas, expected passengers, cargo etc. Subtract this weight from the GVWR on the sticker and what you have left is remaining payload. You may be surprised with how little payload is left for trailer tongue weight.