Sure, but reading OP's posts, he is brand new to using GPG and is importing a single key belonging to ThomasV to verify a single piece of software. He is highly unlikely to be importing other keys at this stage, and even less likely to be using them to build a web of trust since he doesn't know whose keys to trust or even how to sign that he trusts them. Yes, it is a good idea to sign keys once you understand why you should do so (which is explained in the link I gave), but I think forcing him to sign a key when he doesn't understand why is counterproductive to assisting him to safely install Electrum, which is what his ultimate goal here is.