Can I fit a cassette with a larger range with my Shimano Tiagra 10-speed ( GS-4600) derailleur? I'm currently running a 2x10 shimano tiagra 10-speed drivetrain with a 50/34 compact crankset, a 12-30 rear cassette, and a Shimano Tiagra GS-4600 derailleur (that's medium cage aka road long cage) on a light touring / road bike.  

I tend to ride a lot of hills and want a touch more range for tough climbs.  Can I make this work with an 11-32 or 11-34 mountain cassette or do I need to get a long cage derailleur? 

It looks like I might answer my own questions, becuase the specs say, they say I shouldn't really run more than a 30t max in the rear. However, I'm wondering if anyone else has tried this and had success going past spec with this derailleur or if I should resign myself to spending more cash on a new derailleur.
With the b-screw tightened all the way on the medium cage GS-4600 tiagra derailleur I was able to install the 11-32 cassette. It was obvious from the appearance that I wouldn't be able to squeeze any larger of a cassette on the rear wheel without switching to a long cage mountain or touring derailleur.

There were no issues when shifting with the 34t front chainring in or out of the 32t rear cog.   

However, using the 50t front chainring, shifting out of the large 32t cog was a little off. It worked, but it was lagging a bit and having a harder time jumping to the next cog, probably due to the chain being too short since I didn't adjust the chain length.

This should be solved by adding a link or two to the chain. However, I'm going to be swapping in a 46t large chainring, so that should address the lack of slack. I shouldn't even be in the big ring in the back and the big ring in the front anyway to avoid cross chaining.