HUGE loaf of Wheat Bread

For the past two weeks I've struggled with making a tasty wheat bread. Twice in a row, I've made "wheat cake" which was not my intention. The yeast I have should work so I've come to the conclusion that I have either weak yeast or old flour.

I picked up a couple packets of Hodgen's Mill "Extra Rise" yeast and a new sac of Gold Medal whole wheat flour.

I have a favorite french bread recipe that I use. It makes two nice 12" x 3" baguettes:

2 1/4 c flour
1 cup water
1 tbsp sugar
1 tsp salt (optional... adds elasticity)
1 tbsp shortening (optional... adds flavor and denser texture)
1 1/4 tsp yeast

To integrate the new flour and make enough for a tall loaf, I multiplied the ingredients:

4 1/2 c flour
1 c wheat flour (new)
2 1/4 c water (I added some during the mix if it looked too dry after 10 mins)
2 1/4 tsp sugar
1 tsp salt (decided to go with it)
1 1/2 tbsp light peanut oil
3 tsp yeast (fast rise)

I had to make this in two batches (my dough pot isn't quite that large.

While the second batch was being made, I let the first half of the dough rise in a glass bowl gently warmed by a water bath. Once the second was done, I rolled the two together, shaped and put into my loaf pan (dark teflon pan, heavy, measuring 12" x 6" x 5"). Let rise for 30 mins before placing in a 375F oven. I put a pie pan 1/3 full of water in the oven as well to add some moisture. Before I put the loaf in the oven, I sliced it down the middle and sprayed with a little Pam (1/2" deep).

Baked for 10 mins. Sliced it down the middle again (1/2" deep)
Baked for 25 minutes. Removed the loaf from the pan and cooled on a wire rack.

This loaf is over 8 inches high in the middle. I just bought an electric knife, so I can get large thin slices out of this. The texture is very nice (lots of small pockets) and the taste is very good.

Next loaf I make will use more 50% wheat, 50% white and the same yeast as this one.