I Watched Tmob Do his Anomalous Materials run and He Did a Chamber Skip that Skips The Long Xen Scene, I Tried Looking it up But I only Found It For HL1 and not HLS, I've Tried Replicating it but I Can't Seem to Do It Correctly. How Do you Do it?

I Like Speedrunning Through HLS and All, But I feel Like adding A Glitchless Run-type Would make it So You Don't have To use a Trick That Skips the Entire Level, Such as We've Got Hostiles. I Would Like Just playing Through the Entire Level Without Skipping all of it for a Quick, Short Run, While Oob Already Exists There is a lot of Glitches In-Bounds. So I present A Glitchless Run-Type that Disallows Non-intended Glitches, And makes it So You Speedrun Through the Entirety of The Level, Bhopping Can be Allowed but Stuff Like Skipping The Entirety of Power Up Is not Allowed by Using the SMG to Boost over The Wall, You Do it The 'Dev-Intended' Way. (Also Adding this Run-Type to Level Leaderboards would Be Cool Too.)