From connectify dispatch's homesite don't ask how it does it but it works I've seen dozens of videos were people hit 1.2TB\S from a torrent client for example using dispatch as there agent when it comes to mixing WiFi
At Home
Whether you live in a city with Wi-Fi networks everywhere or out in the woods with spotty coverage Dispatch can deliver a faster and more reliable browsing experience. Urban environments are often filled with free hotspots and open Wi-Fi networks. With Dispatch you can utilize them all simultaneously for blazing fast Internet browsing. Just remember you'll need a separate Wi-Fi card for each additional Wi-Fi network you'd like to join - these are some of our favorites. Conversely, if you live in a rural area with slow or unreliable Internet service you can use Dispatch to combine your home's cable, DSL, or satellite connection with your phones tethered 3G or 4G connection or mobile broadband device for smoother and more dependable access.
Unlimited Dispatch Uptime – No time restrictions, run Dispatch 24/7 for a non-stop speed boost.
Application Specific Settings – Set Applications to use only a specific adapter and prevent programs like Windows Update from using up all your precious 3G data.
Connection Metering – Set limits on how much data each interface can use and prevent costly overages on mobile broadband connections
Interface Selection Method – Control how Dispatch divides your Internet traffic amongst available adapters.
Automatic Startup – Start and stop Dispatch automatically when multiple Internet connections are available.
Hotspot PRO Integration - Share your Super-Fast Dispatch Connection with Connectify Hotspot PRO.
Connectify Dispatch lets you combine bandwidth from all your computer’s Internet connections. Got Wi-Fi AND 4G? Two Wi-Fi adapters? Ethernet AND 3G? Dispatch will work with any and all of these technologies to increase your bandwidth. Seamlessly.
Dispatch is particularly well-suited for BitTorrent and web pages - any download that naturally involves multiple files. While monolithic streams like Netflix can’t be split across connections, Dispatch will assign them to the fastest connection - and route other requests to secondary connections. Fast AND smart.
With Dispatch's metered connections you can avoid costly overages by assigning bandwidth caps to your expensive 3G and 4G connections. In addition by setting their Priority level to Backup, Dispatch will only route traffic through them if your Primary connections fail. Fast, smart, AND frugal.