I put clients into plenty of coho every season and I never use bait at all, nothing but spinners, jigs and the odd spoon.
When you are getting chasers on the spinners that turn away its time for the twitchings jigs IMO.
Keep in mind though, that I am fishing out of the boat and not walking the faster water sections of the Vedder. We target Coho in slower moving areas and sloughs.
It is generally accepted that jigs are killers for Coho in all the pacific northwest, the Skeena river and Alaska.
Its is only here in the lower mainland where float fishing roe is still the favored method, that jigs are not taking large amounts of coho.
I have done extremely well on Chinook float fishing jigs and have caught enough Coho float fishing jigs and had many jig customers report back stellar success float fishing jigs to know that it is in fact deadly and far less messy than bait.
I have noticed that Coho are far less interested in bait tipped jigs than Steelhead and just a jig is just as good.
I am not here to suggest that people give up their roe fishing and use jigs, but those looking to try somrthing else, its a great alternative, cleaner and different that what others are using, which can often be the difference.