i did my whole ppl in thick soled trainers as my instructor never told me any different...... another story altogether. when i did my check ride with mike bowden he was amazed i could fly in them..... i found thin soled leather shoes perfect in the air but hopeless around the apron etc...
i resolved to fly in whatever footwear i had on at the time and it works fine..... if in boots just slacken the laces tho.