ZDoom

Recently, I noticed a difference between GZDoom and vanilla Heretic when it comes to pushing those pods around. In the original Heretic, the player was never slowed down (or maybe barely slowed) when pushing a pod around, but in GZDoom, you are. This is why I'm suggesting PushbackFactor, which would determine how much of a slowdown the player receives when you're pushing something. 0.0 means there's no slowdown at all, while 1.0 (the maximum) stops the player every time he makes contact with a pushable thing, though the thing gets pushed anyway.

I doubt this will give you what you want. There is no slowdown when pushing, but the way this affects velocity-based movement, this can result in blocked moves which get perceived as slowdowns.

Sorry, there's nothing that could be done. This is all the result of an originally piss-poor implementation depending on several side effects and bugs in the movement code.

It's strange how it's different for the two versions though. I completely forgot how it worked in vanilla Heretic until someone mentioned it in Doomworld, but there is a noticable difference.

The movement code in ZDoom has seen several changes and some of these actually do interact with the pushing stuff.