Yes I have recently been incorporating shield breaks into my game with a surprising amount of success.
Some somewhat reliable strategies for wearing down the shield are
1. Nair->d-tilt->jab-takes a good portion of the shield and doubles as a trap for spotdodges/shieldgrabs
2. Side B 1,2, and 3 (down)-very large chunk of shield and pretty safe when spaced. The problem is that the pressure is gone right after doing it, so they get more recovery time for their shield
3. Shield breaker
-half a shield gone right away. Problem is it puts the opponent on guard and they avoid shielding. Still you can catch people with this every now and then.
Also, if you want to use more shieldbreaks in your game, it would be wise to take note of where players tend to shield. For instance
Breaking the worn down shield
1. Pretty much EVERYONE shields right after they tech (with the exception of Fox and Falco since they have shines/a good spotdodge). Especially if they tech on a platform above you (to shield the "uptilt" that's coming). If you've already worn down their shield a bit, this is a nice way to make them put it back up and get your shield break.
2. After a whiffed attack-it's common sense that when you whiff an attack you're in a bad position. The opponent is likely going to punish you for missing. Most players will hold shield hoping you mistime your punish/try to punish a move that's safe on whiff and wait to retaliate. They'll do this even with a worn down shield because they plan to go on offense right after. Make sure that you wait to do the shieldbreak until AFTER their lag is over and they put up their shield (if you do it before then they'll see the shieldbreaker and not put up the shield) It also helps to act like you were gonna come in with something else (empty shorthop->shieldbreaker as their shield comes up)
3. Known pressure setups-I'll use the corneria fin trick as an example. On corneria, it's well known that Marth can up B from the ground, grab the fin, and come down with an aerial, all too fast to be reasonably hit out of. Now, to avoid taking absurd amounts of damage, many players will simply shield the aerial and the up B, and then move to a safer position behind Marth (shielding again as the Marth comes down and moving out of range this time). On a worn down shield, this is one of the easiest shield break scenerios, as they're waiting for a specific attack with the intent of shielding it (the extra time where they're holding their shield is just more free shield damage)
Wearing it down (note that the breaking scenerios work here too, the reason I seperated them is because in these scenerios the opponent often has a full shield to start with)
1. wavelanding onto the stage-invincible waveland->shield is a staple getup option for a lot of characters. They're trying to punish your overzelous edgeguard attempt, so make it simple and just do a couple safe on block tactics (retreating nair or the tripple side B are good examples) for some free shield damage)
2. platform light shielding-this seems to be a new trend going around. After you die, the opponent retreats to a platform, goes to the edge, and light shields. The intent is to shield an aerial, slide of the platform, and be able to move away while you're in lag. Now...what if you just throw out a spaced shieldbreaker instead of an aerial? 2/3 of their shield just vanished!
3. rolls and spotdodges-now on the ground, they're more likely to spotdodge/shine cause they're expecting a grab. But if your in the air when they're coming out of it, they're gonna shield. Spacing a shieldbreaker as they come out of a spotdodge or roll gives you a lot of shield damage and is fairly safe, though you'd probably be better off going for that grab anyway <_<
If I think of more I'll let you guys know, but that's most of my shieldbreaker tricks
