Theland //Feathers from scales?
Fossilised scales are found, and fossilised feathers, but no transitional samples.//
Incorrect. Your information is out of date. There are many transitional fossils of dinosaurs with plumage consisting of proto-feathers. Feathers rarely fossilise but archaeologists are extremely dedicated to their work and such fossils have been found.
There is also extremely compelling genetic evidence.
Chicken embryos have literally been made to grow scales instead of feathers and alligator embryos made to grow feathers by simply altering gene switches at a particular time of development. The underlying genes for scales and feathers are the same.
Similarly, chicken embryos have been made to grow teeth by altering the expression of the same genes that are in both reptiles and birds. (The embryos are not allowed to fully develop into hatchlings because of ethical considerations.)
These are not assumptions but solid facts backed up by irrefutable evidence.
https://www.dailymail.co.uk/sciencetech/article-5104527/Scientists-identify-genes-turn-scales-feathers.html