Isolate and Save-As X_T

Here's a new one to me... I modified some parts in Assy. Iused ISOLATE to hide all the other parts then do a Save-As to savethe just modified parts as X_T files. Since it is an assy SW ask ifI want to resolve the hidden parts... I say no... but it saves thewhole assy anyway. Including all the hidden files.

Of course if I manually hide all the parts it only saves thevisible parts.

All these inconsistencies drive me crazy. I had to Saveas the firsttime. Notice the file was huge and import it to see why... Then ISaveas a second time to insure I didn't make a mistake. Andre-import it... Then I savedas a 3rd time and import it to insurecorrectness.

So odd, I'd think Isolate would just Hide the parts and Saveaswouldn't care how they were hid.
SolidworksAssemblies