Yeah as far as I can remember (since 3.0 anyway) this has been a thing, although the extremely situational usefulness + strict timing (if you mess it up, you're gonna eat a BUNCH of percent) makes me never want to rely on it ever in a tournament match. Still pretty cool to do, though.
EDIT: A DC-related tech that I think will be useful is IDC OoS (Instant Dimensional Cape Out-of-Shield). It's hard to do with default controls but I use Z for specials to perform any IDC option quickly and reliably. Starting to incorporate it more in my practice sessions; it's certainly not one of our fastest OoS options but it does cover more space than the others, especially against more powerful hits that send you away in your shield and would normally be safe.
Still playing around with it but I think it could be a thing. I'd suggest giving it a try as well.