- Its never a good idea to split two segments into two reservations. In case of delays or whatever, they have no responsibility to accommodate you.
But that's up to you to decide vs. the 15% discount (or YQ if you redeem with UA or US).
-Yes, a SQ redemption on LH FRA-TLV will include high YQ.
-However there's an interesting thing with SQ, that if you redeem the first leg (JFK-FRA) on a carrier with no YQ (UA) and its on the same reservation with the second leg (FRA-TLV) on a YQ carrier (LH), the YQ on the second leg will be drastically reduced!
You'll end up paying less $$ on the full trip (JFK-FRA-TLV) than on a single half reservation (FRA-TLV)!