Is sticking my feet under the couch dangerous?

i've been dancing for 5 years and my feet have gotten better but Iike all dancers, I want them to pointe more. The arch thing I could care less about, it's just that I want more flexibility in my ankles (especially the left) and my toes to go over more. My arches are low when I stand on then but I can see it more when in demi pointe. The only way i know to fix it effectively is to stick them under the couch. Oh! One more ?, does Linda Celeste Sims of the Alvin Ailey Company have flat feet?