I have had very similar experiences with Wyeast 1968 (like WLP002 - very hi floc, very low attenuation). I have brewed my ESB recipe many times with it, attempting several tweaks to dry it out, get a lower FG. But there seems to be only so much I can do with it. However, similar to your experience, I have a very easy time getting where I want with American strains like 1056. I have a theory, would like to pose to others reading: perhaps these hi-floc strains are best suited for different fermenting geometries and conditions (for example, not a tall slender 6-gal carboy)? One thing I may try next time with my ESB is to pitch two different strains of yeast into the same 5-gal batch, such as 1968 & 1056. Maybe someone has some thoughts on that as well.