I have a general crampon question: I've heard that one main issue with learning to use crampons is their snagging and slicing your pants. Is this usually the front points or the secondary points at the front and sides?
What difference does it make which points are doing the snagging?
Usually when you are wearing crampons you are also wearing gaiters, and usually gaiters are reinforced on the inside leg side as are some pants. Nevertheless, rips still happen occasionally and that's just the way it is, but I suppose with time they happen less frequently.
Rips, although annoying are not dangerous. A bigger problem is trying out a boot/crampon pair for the first time and discovering one of the crampons is no longer on your foot. On a steep section you will likely notice right away, but if steep sections alternate with flatter sections, you might not notice for awhile.
Front point or side points? Both can happen. Side points can easily snag pants as your foot passes by, especially when walking on a side-slope or when carrying a heavy pack, which tend to narrow your stride. It *can* be dangerous if you happen to snag a strong enough section of material to trip yourself. Damage to your pants may also mean increased chances of snow or pebbles entering your boot at an inconvenient time...
Front points snagging are less common but can be worse - if you're kicking yourself with your front points, they'll often embed in your flesh, not just your pants. Injuries in the back country are always fun...
As ZeeJay says, the usual solution is to wear gaiters. Depending on the style of gaiter, these may tuck your pants out of the way, provide reinforcement to minimize rips, and/or have a layer of puncture-resistant "armor" on the surface facing your opposite boot. If you don't have gaiters, duct tape works very well for all three purposes.