My owners manual doesn't specifically address recreational towing, but under the section in emergency towing it limits automatic-equipped Jettas to 30 mph for 30 miles IIRC. It makes no mention of any restrictions for towing manual-equipped cars. The car isn't smart enough to know whether it's being towed in an emergency or for recreational purposes, so I imagine this applies to recreational towing as well.
FWIW, I really like my Jetta. It's a stripped down S model with the smaller engine, but it is quiet, smooth, roomy and economical. Fun to drive with the 5 speed manual. I would have checked out the TDI but couldn't justify the extra $$ for what I use the car for.
1998 Gulfstream Ultra B/H Ford E450 V10
2005 Chevy 2500HD 6.0 w/ Maxidump insert
2006 Ford Escape Hybrid
1998 Saturn SL2 toad
2012 VW Jetta S
You will get very good response and info over at the TDI Club forum. There are a number of good VW TDI techs who hang out there. They will even keep you straight from the bad info the stealership gives you. There are a number of guys pulling pre 2012 TDIs four down. Don't know if they did anything different to the transmission or not for the new m.y.
I have a 2012 tdi jetta 6 speed manual. There is no issue flat towing the manual version. The qwners manual only states you can not tow with front wheels down. This is because of the push button start system. The steering wheel has no key slot so the steering does not lock. this is why people get conflicting info on flat towing a jetta diesel. If you hae the blue ox base plate and are wired up you are good to go with various tow bars as they hae adapters available. There is a lot of misinformation out there but I am setting up to dinghy tow my new jetta and my dealer has no issue with it.