Gain 50 lbs on Bench sounds like a muscle mag article to me. Get RIPPED in 2 days! Add 10 inches to your arms THIS WEEKEND! The secret is inside!
Seriously, 5x5 is what you want for linear progression. If you are stuck try these things in this order
1. Check your diet. More protein and more calories
2. Drop your weight on all 3 movements by 15 lbs. Then start the 5x5 again increasing the load 5 lbs each week. So you'll hit your sticky point again in 3 weeks but you'll be hitting it "running".
3. Do #1 and #2 and take monsterdrol as dabuff describes.
lol. FLat abs only 4 minutes a day!
For the record I wasn't guaranteeing these results. I and others have achieved this or even better results. Talk to Black Boxster. He got even more dramatic gains than I did.
If you are eating excessively calories and you know how to push your limits in the gym, you can achieve a dramatic increase in strength like I have stated. It may not be 50 lbs, but like I said, it depends on where you are starting from.
Lots of people say "Well, I got good gains but not that good." Either 1, they didn't eat enough calories, or 2 they dont know how to push the boundaries in the gym. If yuo have both of those dialed in, you are gonna get big and you are gonna get strong.