Regarding tires, I checked tire pressures routinely and think it is a must for safety sake. When leaving home, the weather in FL was around the mid 80’s when I checked and made sure all tires were at 50lbs pressure which my tires call for. On my first and second stops, the weather was about the same, and my morning tire checks tested the same 50lbs. Then, in SC, the nightly temps dropped to the high 40’s, and when I checked my tires, the pressures on all 4 tires tested almost 5lbs less, ie at 45lbs!
Regarding tongue weight, an old race car mechanic told me that it important to balance the trailer correctly. If the trailer is relatively heavy on the front end, the max tongue might be exceeded but also the extra weight causes more heat and wear on the rear tires of the tv plus more heat and wear on the front tires (of four if you have them) of the TM. So, the trailer should be level. The hitch I had to buy for my last (heavy) trailer allows me to adjust the ball height up or down in order to level the trailer to match my pu’s height, but when the cargo area sags I know I must shift some weight inside my TM (or eliminate something).
When I weighed my 3326, as modified and equipped, but not packed for a trip, the weight was about 4600 lbs. I probably should weigh the TM when packed in order to assure that I am not over-packing (Ha!).
On a slightly different topic, at one of my stops with the ever-present group of set-up watchers, a coach driver in the crowd mentioned that he always weighed his RV prior to any trip because he had had a tire blow on a trip that caused some damage. His insurance refused to pay because he could not prove that he had not overloaded the tires and caused the accident himself.
Regarding the possibility of bouncing the TV’s front tires when going too fast while pulling the TM, I believe this to be true. There are two (at least) really rough sections of I-95 where concrete sections have been laid down very poorly (imo) so that there is a LOUD bump over each section. One such is the stretch from St Augustine up to Jacksonville, FL and another is on one of the long bridges going into Brunswick, GA. On each, I can feel the bounce harmonics building at higher speeds than 55mph with a slight lift up on the front tires. I know to slow down.
“Trailering is a learned skill” is my new motto.