Snape's Memories Again

[Chys Lattes]

No: HPFGUIDX 135663

snip conversation\

JKR: It''s reality. It''s important that I have got that across,
because Slughorn gave Dumbledore this pathetic cut-and-paste memory.
He didn't want to give the real thing, and he very obviously patched
it up and cobbled it together. So, what you remember is accurate in
the Pensieve.

Chys:
Someone asked before on this list (in defence of why DD trusts Snape) 
if a memory stored in a pensieve is no longer in a persons head. (As 
of why DD would so adamantly trust Snape even if he couldn't tell 
Harry exacty why.)

My question is; is it? If Slughorn had placed that cut up memory in 
DD's care, then how come he still has the visible parts in his head, 
so that they can watch the whole thing all together later from the one 
thread that he gives to Harry? 

Or did he only give out the parts he hadn't given him earlier, and DD 
sliced and pasted them together so they could watch the whole unedited 
scene?


Chys