I was coming here to ask for recent experience with this, too. When the dining plan first came back out, a Disney podcast I listen to (WDW Prep to Go) was able to do it by asking the server to split the check, which allowed them to process two sets of two DP TS credits. But I would think this is a YMMV thing, because it is clearly trying to get around what Disney had intended, so I was curious if they had cracked down on this.
Relatedly - does anyone know if there's a limit on using QS or snack credits at once? Like if there are only two of us on the DP, can I use 4 QS credits at the same meal?