yes If you already have it...(it might be in your program files directory) then simply copy it all to a new directory in your My Documents and then put Tequila.exe in that directory and run it. If you put it in an empty directory, it will download the client. If you copy your old one, it will simply validate.
To amplify: if you do not have the City of Heroes Issue 24 (beta) client, then you download Tequia, make a folder somewhere and put it in there, then run it. Tequila will download Icon, Paragon Chat when it becomes available, and the entire I24 client into that folder.
However, that could take a while because while Icon and (presumably) Paragon Chat are relatively small programs, the City of Heroes client is pretty huge relative to most people's download speeds. And that speed will probably get a lot worse as Paragon Chat releases and people start all trying to update everything at once. If you do have a copy of the Issue 24 client and therefore don't need it again, you could copy Tequila into that directory, whereupon it will just verify your game client files and only download what it thinks it needs (if a file is missing or damaged). If you don't like the idea of Tequila messing with your game client files or are not sure which version of the client you have, just copy the contents of your game client folder into the Tequila folder, and then run Tequila. Tequila will check all those files, and if they are the I24 files it will not download them again. If they are not the I24 files or they are broken in some way, it will download what it needs. And since this is happening in a different folder from your actual I24 client, there's no possibility of breaking anything you already have. You do need enough space free on your hard drive for two copies of the game client though - about 6 gigabytes or so for the minimum necessary game client set.