Of course they could say Henry VII's right to the throne was by right of conquest (winning the battle of Bosworth Field in 1485), just as William the Bastard became king of England by virtue of winning the battle of Hastings. There was a taint of illegitimacy in the Tudor line anyway--an ancestor had been born illegitimate and later legitimized.
The Wittelsbachs have a better genealogical claim to the throne than the Saxe-Coburg-Gotha line anyway, but also going back to Henry VII.
"The Wittelsbachs have a better genealogical claim to the throne than the Saxe-Coburg-Gotha line anyway..."
They're in my family as well as the Hapsburgs, the Dillenburgs, and the Hohenzollerns. Never knew until I had my DNA done that there was any German or Italian in my family. My DNA showed 35% Germanic Empire.