I think that advice about avoiding water is in early spring when water is still in 30s and 40s.And,clean water that time is usually difficult to even find.But if you do have clean water,it is usually a couple degrees colder than any nearby stained water.A great place to fish is where that transition of color is located if you can find it.And yes,trust your electronics.If marking fish,give it a try.A few years ago was fishing in early spring and asked Captain Keith from pooh bear charters where to fish.He told me to stay out of the clean water.Not catching there with the cranks he was running.