Shooting FP4 at EI 200

Someone posted that they had tested and rated FP4 at a true speed of 200. If this is correct, the 125 EI is an artifact of development times. I note that Ilford posts processing times for 200 inside the box. If one is processing any size (35, 120, 4x5) FP4 in D76/ID11, how well does it perform at EI 200 in general? Does it do better across the board with a full strength solution, or a 1:1 dilution?

Just to mention that on the Diafine box they rate it at 250. I usually see people down rating it to 100 or even 80. I always shot it at 125 with development in Xtol 1:3 per recommendation in the Film Developing Cookbook and the negs came out very nice. I basically abandoned it because of it's low speed, but now that I see the Diafine rating I may try it again.

The film speed depends on the developer used; it seems that "traditional" emulsions like FP4+ are more variable than the T-grain/Delta and similar emulsions.

I rate FP4+ at 80 for Pyrocat-HD, 125 for D-76, 200 for FX-2 and 250 for Neofin Blau / Beutler's. Or I just shoot it at 100 and hope for the best...

I rate fp4 @ 160 and dev in rodinal 1:25 for 9minutes. I print on an omega D2 with Dichroic head.