Short description of error
Depending on the chosen Shapekey, The intersect(Boolean) operator will fail or not to take all loopcuts.
Exact steps for others to reproduce the error
Open Attached .Blend. If you call intersect while in edit mode with shapekey "ok", it will succeed to take all loopcuts (see cut in image's top left). If you take the shapekey "bug" some loopcuts will be missing (see arrow in picture).