You are absolutely correct. I would only point out that this is true for all options. Delta should always be calculated based on the forward price of the asset that matches the expiry. I guess people tend to forget this fact because rates have been so low for a considerable period of time, making forwards to be very close to spot. Obviously, VIX forwards are much different from spot.
I was mucking around and came up with this seemingly interesting strategy on Intel:
http://tm.cmlviz.com/index.php?share_key=P8RI8fUXk45tfzZY
I sell straddle on Intel right after earnings for 29 days. The premise is that Intel stops moving too much after earnings.
@Kim,
Is there a way to track a portfolio of multiple options of different underlyings in ONE software? I just got the trial subscription to ONE but I can't seem to be able to see a way of doing. It allows only multiple options of the SAME underlying.
Thanks