The poo boots were the "interim" boots - I still have an unworn pair in the garage.Christ, that's embarrassing. I remember the boots saga. I was one of the last to get issued black gp boots in my battalion. They were brilliant.
Then came the brown boots that you had to smear in dubbin to keep them waterproof. They were meant to be an "interim " boot until new, sexy boots were procured, hence the cardboard inner soles. The "interim" boot stayed around for about 10 years iirc.
They started out being a nice shade of brown, but later production runs were green.
After them came several different "trendy" boot designs, all of which were hopeless.
Everyone just wanted to go back to Black GPs.