>>536577165
Every viable plus on block special is useless because all foxfires can be spotdodged and it's a generally unfavorable choice of either 22L leaving you at +0 on block, 22M leaving you at +5 but being the slowest and easiest to respond at 31 frames and 22H leaving you at +4 but not perfectly linking into any normal other than c5H.

Thus Yuels typically tend to constantly frame trap from neutral with f5M into 22L which isn't useful or will instead end block strings instead on 236L, which whilst leaving you minus at -3, leaves you far enough to gap with 2M, but this is also a gamble, OR they can end in stance with st.5L usually beating f5L responses but loses to M buttons and most every other stance button having some specific use case where they win against 1 button and lose to 4.

Thus, Yuels, knowing the opponent will press a button knowing they are plus, will throw out either a 623L or 623M/H due to the different properties. 623L, whilst not having invincibility, and sharing the same crush levels as the other DPs, can keep the flow of the match in your favor as it's harder to punish with strong starters unlike 623M/H which you trade safety on block for invincibility to get out of pressure.

You can also cancel into 22U to stay safe, even on BC, and leads into instant mixups, but that's 50 meter which isn't always available.

TL;DR
Yuels specials are generally minus on block and the only ones that are plus are resource intensive or don't work like they should. Thus the opponent can take their turn back with a simple light attack, meaning that it's sometimes the best option for a Yuel to mash DP, because if it connects and they are knocked down, even for a second, they can access stance and go for mixup.

Yuel is a knowledge check character, where she won't kill you in 2, 3 or even 4 hits. She'll kill you in as many knowledge checks you fail (unless the Yuel is retarded and throws out a bad Ult skill or fat fingers ex foxflame when they meant to retreat)