Mesh Renderer - Scaling Limits - ?

Anyone got an absolute idea as to what the limits are for scaling down a Mesh Renderer patch?

I ask as I've just had a crash that seems to be totally related to using very small scaling [0.0004 and lower], worked for a while, then crashed whilst scaling a dynamic mesh.

Static meshes seem far too stable for this to occur, but your mileage and experience may well vary.