Originally Posted by
Zorak
Not specifically with Hilton, but in general multiple AMEX offers stack with each other (and with annual credit rebates etc.). Personal experience with DL and Marriott.
IMO the 20% by itself is sufficient inducement and if you get the extra $150 then so much the better
If you're asking about the "charge to the room" aspect, there also IME AMEX looks at the total amount charged to the card and does not distinguish between base rate, taxes, and room charges.
Yes, no complaints either ways. I would have taken these on separate cards as well.
I found a different Hilton offer on yet another card

Now I will need to request split billing on two different cards.
Wonderful partnership there b/w Amex and Hilton.