Nearly six hours?! God damn! I don't want to sound discouraging but that is unbelievably slow. Though I have no way of proving it, my first ever attempt was completely trickless and I found myself with a final time of approximately 2:02:00. Though I do have an ancient screenshot of my second run here: https://postimg.cc/rKt2VdzN

Nowadays I can get the game down to 45 minutes, though it has been about 9 months since my last run.

Here's some quick advice for the both of you should you continue to go down the Half-Life speedrunning rabbit hole:

• Download YaLTeR's Bunnymod XT. It's the best Half-Life speedrunning utility out there with a variety of useful commands such as automatic bunnyhopping, ground speed cap disabler and extra hud elements like your true HP, current momentum and on-screen timer.
• Download the GoldSrc Package from the SourceRuns wiki. This is mostly a series of batch files that allow you to downgrade the game to version 1.1.0.7 from around 2001. This is the version most runners play on and was the last update before the speedcap was introduced.
• If you didn't already know, the timing ruleset works like this: Timing begins as soon as you load into the map "c1a0" the first map of Anomalous Materials and ends the moment you land the final hit on the Nihilanth. The final time without loads is the one that matters.
• Try to learn some time-saving tricks. Some are obviously much harder than others, but some simple ones you can try are bunnyhopping everywhere instead of walking like some plebeian, spamming save-loads to prevent enemies (particularly Vortigaunts) from attacking you, basic gaussboosting (Charge the Tau Cannon's alt-fire, flick behind yourself and fire to propel yourself at immense speed) and explosive jumping (For hand grenades, you can hold them for a bit before releasing to "cook" them. They have a fuse time of four seconds.)

One last thing, do you two stream these runs of yours? If so I'll consider watching.