I've been experimenting with the above combination and find that the warmth effect goes from being non-existent to being very noticable . The container says the warmth effect is most pronounced at 1+30 dilution and high temps (20C + ) .
However last night I got the warmest ever effect on my paper (esp on Pearl) near the end of my session .(I loved it BTW) . By then the developer was at its coldest (I had mixed with warmish water) . I suppose it was nearly exhausted as I had done about eight 8x10 's at this point .

Anyone have any experience of this combination ar this happening?
Was it a kind of lith chemical effect ?
Should I be bottling some of the old developer like "old brown"??

Please dont reply "use another paper" - I know actual warmtone paper will give a greater effect -I'm just curious as to why this happened and is it repeatable. Thanks guys (and gals)