About the Side Guard Break

So i was doing some test after a discussion with my buddies and turns out Akira's and Lau's guard break on a side turned opponent aren't really at +17 as they should be but they are like +20. I don't know if the cpu can't guard properly or if there's something i'm missing so if anybody here can explain that to me i'll be really gratefull.

 

I went to dojo and did a OM to the side, then did the guard break with both akira and lau. The guard break enters (cpu blocking) and gives me +17 so every hit that is 17 or less connects without any problem. Then i did the yohou with akira and it CONNECTS tryed with hits that are 20f exe and still connects, but with 21 the party is over. This is true both for akira AND lau chan.

I tried the same thing with wolf (+9 front +11 side) but got no luck. Still need to test it with brad, goh and other guys with a possibile scenario where they do a side guard break.