My figures are without trim tabs, for what it is worth.
If someone is getting 1.4 gph at 7.1kts they likely have a different engine. Mine is a Volvo Tamd 41PA - 200hp. There is no way I can achieve 1.4 gph on my boat.
I often see inflated fuel consumption claims in sellers ads. Need to be taken with a proverbial grain of salt imho.
Good luck on Thursday!