I actually don't really agree with this. It's important for the Democrats to be pushing bills that would be good ideas. No, none of them will pass or even get out of committee, but having them written is healthy for the party. Today's example should make clear what happens to a party that spends years running on opposition without having actual practical policy proposals to pass when they get into power.
I have no problems with Democrats doing this, and agree that they should be putting forth workable policy proposals to the floor.
My point is that they shouldn't go on all the news channels and focusing on decriminalizing marijuana as a political strategy to show that Trump doesn't keep his campaign promises. What the OP is talking about is creating a media narrative, and that takes a significant amount of time and effort. And that time and effort is simply not worth it when you have the gift of Trumpcare.