Tom you are exactly correct you can either cut off the green wire or put the end of it under the screw where the white wire is connected.

Unfortunately it's a big no-no to connect the neutral & ground together on the load side: 

"The National Electrical Code requires a neutral-to-ground connection to be made at service equipment only and there shall not be any neutral-to-ground connection on the load side of service equipment [250-23(a), 250-24(a)(5)], except as permitted in Section 250-61 [250-142]." 

You need to use all four conductors of your receptacle/power cord to comply with the code.

Tom I read your first post too fast, and as two other folks noticed, the existing green wire does NOT go back where it was, I though that you meant that you were going to put it on the screw where the white wires go which is what I said in my response. And while you could just cut off this green jumper-ground wire the preferred place to put it would be back on the white neutral terminal in case someone wanted to use the dryer with a 3 wire hook-up in the future.

Clever idea Martin, I guess it was only a matter of time till someone came out with these. They sort of glossed over what to do with that green wire that needs to be connected to a good ground in the video when converting a older 3 wire outlet to accept a 4 prong plug, LOL.

I wounder how soon that manufactures will start warning consumers not to use an ADAPTER, like they have done with the 120 three pronged adapters for the last 30 years.

The bad thing about these adapters is you have two HIGH CURRENT connections stacked on top of each other, which will more than double the risk of heat build-up and failure or even possible fire at the outlet area.