Just do it. It's harmless unless you're planning to get something in the same rewards ecosystem with Citi for a SUB.
By that I mean if you're collecting TY points and make a change outside of that program it will trigger a 24 month clock on getting a bonus within that program. Otherwise if not, then just do it since it takes them forever to send the new cards out while counting down the 45 day rescind period in which you can switch back w/o any changes made.
Yeah, the only issue people run into is when they chase the SUB for new accounts and don't know about the 24 month clock. PC's are painless and Citi doesn't really grow all that much for most of their low level legacy cards which is why the "glitch" was so popular. Most of their growers seem to have AF's attached to them. 4K is pretty good for the cards we have. I tend to get 2K increments with them when other banks offer so much more. I'm planning to combine or as they call it reallocating my limits later this month after my SP CLI. I might wait until next month as the other card will also be eligible for a SP CLI as well. Since the shuffling requires a HP anyway I'll push them for more during that as well to see if they'll actually loosen the purse strings a bit.