There's no need to use the carve tool when clip is that much more efficient.
FYI: clicking the clip tool
clippingtool
1, 2 or 3 times swaps it's cutting mode (removes left of cut, removes right of cut, does not delete but keeps both sides of the brush when cut). The third option is the one you should use most of the time and creates holes in geometry just as fast and with a greater amount of control.
Carve is not bad by default but it causes so many geometry errors, "texture perpendicular to face" and "invalid solid" being the most common, that the amount of post-carve-editing required to fix it's mistakes actually makes your job harder and the potential for unnecassery errors that much greater, especially as a novice who is not used to vertex editing or applying textures in non-standard ways (not "to world"; ie carve has the tendency to create faces that have an infinite plane on a particular axis; and just as awkward, these textures are not always visible but hidden behind other geometry and take a while to find).
Valve havn't used this feature since the days of Quake, they just havn't bothered removing it yet. Any sensible mapper will avoid it.
I havn't touched it since 1999 and the bugger should have stayed on other side of the millenium.