Very Interesting Andrew. I see that the A bey seller of Nyogel 767 now sells the green as a replacement because Nyogel has been discontinued.
My Mk 6 Airsporter leaked like a sieve and blew Nyogel out. I ended up getting two small grooves cut and o rings fitted to hold it in. Even though some air can escape out of the loading hole it did make a positive difference, as shown when releasing the cocking lever against an open tap.
I will be interested to see how the green and blue compare and whether the blue stops the tap moving.
The first few pellets may drag grease into the bore and reduce velocity.
The more I think I know, the more I realise the less I know.