There are still some flaws in CS:S which don’t reflect real world in any reasonable way. The game isn’t supposed to be 1:1 realistic in respect to real world but these bugs / flaws in the game don’t make any sense even in the virtual world.

1. Bunnyhopping

It’s possible to boost player’s speed by jumping to sloping surfaces. Jumping at the right time when going down ramps will boost player’s speed significantly. Better players can do similar boosting even on seemingly flat surfaces where there is only small leaning next to walls. Valve did try to disable bunny hopping by slowing players down after they fall on the ground but that doesn’t work if players are on sloped surface.

2. AWP quickswitch reload

It’s possible to reload AWP faster than normally by pressing “lastinv” button (default: q) twice very fast. Right after AWP has been fired rather than waiting for normal reload animation to take place player presses “lastinv” twice. It is faster for player to switch to secondary weapon and then back to AWP to get his AWP reloaded than wait for AWP to reload normally. Reload time is around 85% of normal AWP reloading. Some players tweak “lastinv” to one of their rarely used mouse buttons so they can press both “q” and mouse button at the same time to achieve fast reload. It is also possible to create script which fires the whole sequence just by one key press.

3. Invisible roof on maps

In each map there is an invisible roof on the maps. Grenades can pass through those obstacles but player models hit them. On some maps purpose of these invisible roofs is to prevent players from climbing too high by hopping on top of eachothers. On de_dust2 the roof is one of the most irritating. On bombsite B player can easily reach the invisible wall by jumping on the boxes near hole in the wall. The roof effectively disturbs normal gameplay for no apparent reason.

4. Flashbangs do not affect if thrown too high

On most maps it’s possible to throw flashes and other grenades above walls. However flashes don’t sometimes affect anybody if thrown too high even though otherwise they would blind everybody around.

5. Grenades through walls

On some maps it seems to be possible to throw flashes through rooftops or walls. On de_dust2 it’s possible to throw flash over the building near bombsite A so it flashes players on the other side near the slope. This is yet to be confirmed but it seems that throwing flash so far is not possible. Flash should drop on the roof of the building. What may be happening is that the roof has not been modelled and thus grenades can pass right through.

Miscellaneous stuff

There are other things too. Here’s a short list.

  • “Bad netcode” which people constantly whine. That might not be as easy to fix as people make it seem like. Related to this is “bad hitboxes” which is also another thing which most people don’t have a clue about.
  • SourceTV demos don’t show player’s view as it is seen in game. Every second update to CS:S seems to break compatibility with previous demo files and clients too.
  • Quickscoping with AWP. Pressing right mouse button just before firing with AWP is something on the gray area. Without scope bullets aren’t so effective and very inaccurate. If player manages to press scope on just for a brief moment before firing it will be more accurate and give more damage than firing same way without scope.

I’m sure there is more.