I think firstly, that a skater must feel comfortable with his/her program. If after several practice sessions with the original choreography and there is hesitation by the skater, then the program MUST be tweaked. Additional tweaking will take place as the skater performs in lesser competitions. I'm sure that will go for every skater unless the coach is also a choreographer.
MK's fault, imo, was not the tweaked program but the lack of MIFs in the program. However, I can say that just about every skater. Spread Eagles and Ina Bauers are, for me, elements and not MIFs unless they are a preparation for another element.
What I like to see in MIFs are the basics: Three turns, brackets, rockers and counters, etc should be interspersed throughout the program and not just in the special footwork.
Johnny Weir has the best basics in his programs. Every crossover sequence is met with a series of basic turns. Of course quads and 3As have to be done at high speed and carefully.
Joe