Why?

[Tariel Gogoberidze]

on mouseUp

   Put "N,33,0,No Answer" into line 1 of TestLog
   Put "N,11,0" into line 2 of TestLog

   repeat for each line LL in TestLog
     if last char of LL <> comma then
       put comma after LL
       -- HERE LL with line 2 of TestLog gets replaced
       -- by previous LL which was holding line 1 of TestLog
     end if
     add item 2 of LL to tTest
   end repeat

   put tTest

   -- returns 66 instead of 44 that one might expect

end mouseUp

I was getting inconsistent results in large script and it took me a 
while to narrow down the bug to the script above. I can work around this 
phenomena of course but just curious why is this happening?

Best regards
Tariel