Forgot, in the spring use a smaller fly to imitate the hatching forage fish in the water you are pike or musky fishing.
Thats what I did when looked that monster musky on the Chippewa Flowage, Wisconsin five years ago.
It only took me three years to figure that out.
You owe me a beer some time. I do think the smaller streamers work in the spring better. Lots of experienced musky fisherman were throwing smaller lures even in June up in wisconsin