kadee magnets work best for me if i remove the ties and build a platform from strip styrene to mount the magnet on. that places the magnet at rail height instead of just above like kadee recommends. i started this method when my atlas locomotives began snagging the magnet with the close clearance of their gear box covers.
all my layout is operated with FM walk around remote control and all the switches are hand thrown so a coupler pick is the most common method of uncoupling used. i find the rix magnet uncoupling tools work pretty well also.
magnets are used only on some of my industrial sidings and spurs and at strategic locations in the main yard.
the main yard has 11 double ended tracks. 4 a/d, 6 classification and 1 running or by-pass track that remains clear. only the classification tracks have magnets for uncoupling and only on the drill track end.
of course, the delayed action sometimes results in having to couple up the track or "make the joints" just like we did in the real world but that is a common everyday occurance in switching anyway.
cars from the class tracks often get set over to the a/d side of the yard by a "trimmer" engine that works off the lead at the other end of the yard. in that operation, just like when shoving cars into industry and interchange tracks, i use the pick or rix tool to cut the engine off and sometimes uncouple it from a convenient location with a pick, use the pick to offset the couplers and then shove the cars to the desired location.
this next statement will open a can of worms with some guys but here goes. KADEE-KADEE-KADEE !!!! you are asking for trouble if you mix the different kadee clones with the original thing. acumate, mchenry, etc. are truly miracle products. when they work as well as the original kadee's, it is a miracle.
and now for a final word on achieving dependable operation. lube the draft gear boxes and knuckles with some form of graphite. i like to use a liquid product called neolube. i apply it with a small paint brush. the alcohol evaporates right away leaving a coating of graphite and teflon on the parts.
good luck and never give up. with a bit of practice and some more experience, things will work out well for you.