I just found out something that others might be interested in. To save people downloading all of Mr Gray's tree libraries when I might only use a couple of types, I've taken the textures in question and made them into 256x256 8 bit bmps with black backgrounds and applied transparency in EOD. Putting the results in my scenery\texture folder worked fine.
I then thought - what happens if a make the textures extended bmps - 16 bit 444 with alpha as that's what EOD likes.
Result - just 1 tree gave a saving of 0.2k - not a lot you say but not bad in total when you might have dozens of the little devils all over your scenery.
Then I thought, what about all my other custom textures which were all 256 or 512 8 bit bmps. So I converted all of those to extended 16 bit 444.
Result - an FR increase of 1-2 f/s. May not sound a lot, but this is in parts of the scenery where with AI and stuff FR was down to UNDER 5 and nearer 4. In other parts where