Cons (and pros?) of linking pitches
“The topo says the next pitch is 30 meters, and the one after that is only 25. Let's link both of those together!”
Are you itching to put your new 70 meter rope (or maybe fancy 2 way radios) to full use? Many people think they can save time (and maybe get some style / coolness points?) by linking pitches.
Linking pitches might sound faster, and occasionally it can be.
But it usually comes with some downsides:
Communication (verbal and visual) is more difficult
Increased rope drag
Usually need a larger rack; more gear is heavier
Potential of a longer fall because more stretchy rope is out
Potential of a longer fall because you may be short on gear and need to go farther between good placements
Risk of running out of the gear you need to adequately protect the climb
If you want to increase your climbing efficiency, it might be better to focus on improving your belay transitions rather than linking pitches. If you only spend a minute or so at each belay changeover, you may find that climbing the route as “designed” is actually faster and less hassle than trying to link pitches.
Some ways to increase overall efficiency:
When cleaning, keep the gear reasonably sorted and tidy.
The leader keeps the rope stacked carefully, coiled or knotted on a sling or carabiner, or even in a rope bag.
Swapping belay devices is a good trick for faster belay transitions.
Conversely, if you have challenging conditions, like low visibility or high wind, you may want to make the standard pitches even shorter, so you can maintain visual and verbal contact. Maintaining visual contact is an underappreciated way to increase team efficiency in lots of small ways. For example, the belayer can usually see when the leader has stopped and is starting to build an anchor, and then the belayer can start breaking down their system and getting ready to climb.
Consider using the so-called “silent system” of belay communication to minimize yelling and keep communications clear.
You MIGHT be able to climb more efficiently, by linking pitches if everything is in alignment, but it doesn’t always lead to a faster or less risky climb.
Did you climb a route in five pitches instead of seven? Sorry, that doesn't make you cooler. =^)