Impending doom for LTE?

I purchased a LTE device from Verizon in December, when I purchased the phone I was getting speeds of around 25-30 Mbps down and 15-20 Mbps up. As more people started using the LTE network, the speeds became continually slower and now I get from 4-12 Mbps down (Of course the 4 Mbps comes during traffic hours on Fridays.) and about 14 Mbps up.

This made me start thinking though. There are multiple rumors about the LTE capable iPhone 5. Almost everyone agrees that it will have LTE, in fact I believe it will too. However, with the amount of iPhone sales that wireless companies make, you can't help but wonder, will this have a great impact on the speeds of LTE? There is always the possibility of increasing the backhaul at the towers so the load won't be as heavy, or Apple might do what Opera does and compress the data packets for faster and less data intensive usage. Overall, I am expecting for both AT&T and Verizon's networks becoming bogged down from all the usage, like AT&T's 3G network was when the iPhone 3G came out.

Both of those networks are focusing on building out their networks, and I currently don't think they are going to focus too much on increasing backhaul at this point in time. I wouldn't be surprised that once the LTE iPhone does come out I can expect to see even slower speeds of 6 Mbps constant and about 8 up, and I still don't get why the upload speeds are currently always faster for me than the download speeds. I'd like to hear some other people's opinions on this and perhaps some insight on it too.