Uh... Who is mad, or desperate enough, to use torrents on a unreliable, slow and capped as hell cellular connection?
I can't speak for where you live specifically, but here in the northeast, I can tell you this much:
1.) T-Mobile is, in most metro-ish areas, as reliable as any other carrier. Also, it's not beyond the realm of realisticness to presume that users torrenting on their phone aren't torrenting while driving - if you're stationary and have four bars of LTE signal, T-Mo is pretty damn solid.
2.) I've gotten 2.5MBytes/sec down on my phone. Not during peak hours, of course, and somewhat varied based on what tower I'm connected to, but >1MByte/sec is quite common - and triple the speed of my home DSL.
3.) T-Mobile still offers kitchen-sink unlimited data plans if you pay enough. On those, they have a cap on tethering, but on the phone, you can download as much as you want. Since Android has a handful of bittorrent applications, it's entirely possible to be torrenting on an unlimited, uncapped data plan.
I don't blame T-Mo for doing what they're doing. Torrenting, by nature, takes a significant amount of bandwidth, requires lots of network connections, pounds the Carrier NAT with connections that can't be completed, requires a metric ton of extra routes, and doesn't stop seeding unless the user sets it as such.
If there's a protocol that's terrible from a cellular provider's standpoint, it's bittorrent. Blocking it on cell phones is about the least objectionable form of "network non-neutrality" that a carrier could implement. On a similar note, I don't know that T-Mobile's music streaming policy is terribly unfair, since they're whitelisting all the major streaming music providers. If they made Pandora free while Slacker had to pay, that's not 'net neutral'. Since everyone who streams audio is included, it's a blurry area for net neutrality.