Looking at flying dub to SGN next july. The flight stops at BKK for an hour or so onroute. If I book the flight on two tickets Dub to BKK and BKK to SGN its significantly less expensive than Dub to SGN direct in C. Is there any reason i cant do this??. I assume since LH shows the fare that they have the rights to fly people on a separate ticket BKK to SGN?

I assume bags etc would go though and that id get all boarding passes etc when i checked in in dublin.

thanks