We did a 4 way split stay in June, and I have to admit that I never checked my cc statement online to see what all was put through as holds and when we were charged. I followed this all before I went, and then once we got there didn't change anything with what I did and didn't notice any difference compared to previous stays. We had it split 4/4/5/1, and I believe I was charged 4 times, each at the end of each leg of the stay (except for a couple of charges that I had them do at check in, keep reading for details).
However, there was one noticeable change to me that did actually make a difference to us (it probably wouldn't to most people). We always do room only and only pay the first night deposit ahead of time, we pay the rest when we get there. I just don't see any point in giving Disney my money before I have to. In the past they have always charged us the room balance when we check in, and then put through the magic band charges at the end of the stay or when you reached that pervious threshold that varied by resort level (I think it was $2000 for deluxe most recently). Now they only do a hold for the room total that you owe plus the $100 extra hold, and don't charge anything when you check in. You pay it all at either check out or on the 5th day if you stay is longer I guess, and then at check out pay what you charged past the 5th day? It doesn't seem like it would matter, except that we wanted to charge the room to one cc to get a cc benefit from it and put another cc on our room for the MB charges. This really threw them for a loop.
When we checked into the BWI I didn't know things had changed, so I gave them the cc we wanted the room on and told them that. She said something about how they don't usually do it that way now, but since I didn't know things had changed I didn't realize what she meant. She asked me if I wanted her to charge it now and I was just confused and said yes. So she charged it and I gave her my Disney Visa for room charges, not realizing things were different and thinking we had just not been understanding each other well or something.
So fast forward to when we were checking OUT of the Poly for our second stay. I assumed I had paid the rest of what we owed on the room when we checked in, like we always have, but it turns out that was just the hold. I don't know what the CM had thought I meant or how he thought it would work when I told him and check in about using 2 cc. I guess he just ignored me? So our room AND all of our charges had still not been put through yet (I have no idea why, I thought it would have been done early AM of our checkout day which was also day 5). So they weren't able to put the room on one cc and the charges on another without a HUGE hassle. In fact the cc they had on our file was an old one I didn't want to use at all! Despite me telling them at check in that I wanted one cc for the room and one for incidentals, and I presume (I don't actually remember for sure) inserting both cards for them. They were pulling out calculators and trying to go line by line and add up the taxes, etc. (We had a lot of MB charges as well as each room night, parking, and all of the separate line item taxes per night) I was too afraid they would make a calculation error that way and just had them put it on the cc I wanted to use for the room, and had to forgo my disney points. They also checked us into our GF stay at the Poly, and I insisted that they put the room charge for our GF stay through then on the cc I wanted, and then put the second card for charging. But when we actually went to the GF later that day they hadn't done it correctly, and they had to change it. I had to give them the cc that I wanted the incidentals to go on, they still had that old card showing despite what the Poly had done. At least the actual room charge had gone through correctly. At the GF she made the first mention of things being different, saying that now they do it all different and that a lot pf people aren't used to it yet and they are seeing a lot of errors.
Now that I know how it's done I know to either call and pay the room off before we check in if we want to use 2 different cards, or at least make sure they go ahead and charge the room (not just do a hold) when we check in before we have any MB charges and then put the second card on the room for charging.
I did notice at the Poly when they did the charge for the upcoming GF stay I had 2 charge notifications on my cc that went to my apple watch - one for the room total that I presume was the actual room charge I had them put through and one for $100 more, which I presume was a hold. So I had over $5000 go to the cc right then - one was a charge and one was a hold for the total plus $100, even though we had just paid the total. Immediately after we had the charged from our entire Poly stay go through, that was quite the hit on our cc all at once!
So, crazy long story short, it we hadn't wanted to use 2 different ccs for the room and incidentals I wouldn't have noticed anything different without checking my actual cc charges online. However, because of the specific circumstances we had (wanting to use 2 cards and not having them charge the room first at the Poly) it did become quite the issue. We did charge pretty much everything to out MBs throughout our stay.