Ha! Funny you should ask... I won't say "stay away from paddling", but I will say "I'm a believer in surgery".
I'm currently 5 weeks post-shoulder surgery and hope to be back in my boat, throwing ends in Charlie's Hole, on May 1st.
I too had extensive impingement (in my right shoulder) that impacted my ability to paddle. I had a bone defect (type-III hooked acromion process) on my scapula that caused impingement to my sub-acromial bursa in my shoulder joint. Any type of overhead activity (skate skiing, paddling, mountain biking) caused severe aggravation. I was also having problems with both hands and arms "falling asleep" at night while lying in bed.
I tried cortisone injections and accupuncture, which help the pain and inflammation, but not the cause. Finally decided to go the surgery route (thank gawd for medical insurance but my 2K deductible is now kickin' my ass!). My orthopedic (Bryan Bomberg of Steamboat -- also a paddler!) did a sub-acromial decompression (removed some bone), as well as removing some of the inflammed bursa. All done arthoscopically with only three small puncture holes in my shoulder. Luckily, no rotator cuff or labral tear was involved. I'm definitely a believer.
Here's my doc's website:
Email me if you want more first-hand info about my surgery. I'd also recommend:
1. Lots of pre-season shoulder strengthening using a thera-band
2. Get out of the playhole BEFORE your tired
3. Ice & Ibu afterwards
4. Get a soft, flexible paddle (seven2)