Originally Posted by
Lomapaseo
I don't see the problem with IRROPs since the implication that you have already used a ticket and that Delta will make good on getting you to your destination for that ticket. On the other hand the worry may be on a Weather cancelation before your trip. In that case they may offer to rebook or refund the one way fare only. Although I might expect them to offer to credit you for both tickets (not refund) if you can talk them into it.
My earlier post applies to this as well. On a single RT ticket, IRROPS or weather waiver will easily and without fuss be applied to the entire ticket (even if you want to just cancel the trip altogether).
On separate tickets, you'll almost always find agents who will understand your plight and treat the two tickets as one, but it requires them to manually override the system so it a) creates an extra layer of work for both pax and agent, and b) requires you to call in during a time when hold times might be longer vs. just self-servicing online. And at the end of the day, they aren't necessarily required to treat it as a single ticket, so DL could say the weather waiver is good to change/cancel your outbound but you're stuck with the return as-booked unless you pay a change fee; and you'd have no recourse other than HUCA.
TL;DR, unless the price difference is extreme or there's a very specific reason that you need to manage the tickets independently (e.g., only one direction will be expensed and your client/employer is a stickler for matching receipts), it's almost always better and easier to book simple RTs as a single ticket vs. two one-ways.