Hi Michael,
1- During provisioning the host attempts to keep files contiguous, but it truly depends on the how fragmented the volumes are. As you can imagine a SVMotion of a vmdk will punch a hole in the middle of a volume and host has re-use the space. So answer is "it depends", it may or may not be contiguous.
vmkfstools will display multiple ranges if its non-contiguous.
2-As long as the vmdk files are not locked(VM powered on) , this should work.