Question

Two loaves with bread formula using all-purpose flour. Proof, makeup, second rise then 375F with no steam x 42 minutes. Excellent result. BUT, about half the time, the loaves rip apart on one long side as they rise in baking. 
Completely unpredictable. One, none or both. 

Fleischmann make-up = slap out a flat, elongate pad and roll up to bake in standard pans. 

Thank you. I cannot imagine why this happens.

Answer

Baked breads crack and tear resulting in an uneven break and shred. In pan breads the break and shred refers to the crust separation between the sides of the loaf and the top crust of the bread. Quality bread has an even break and shred. Uneven break and shred may be due to such factors as: 

1. Lack of steam in the oven before loading the bread 
2. Extremely hot oven temperature 
3. Uneven molding which leaves open dough seams 
4. Lack of proof, dough that is too young or old 
5. Pans that are not greased or properly prepared causing the dough to stick to the sides 

In the case of hearth-type breads, the most common causes of uneven shred are lack of proof, improper or uneven cuts made on the surface of the dough, and insufficient steam in the oven at the time of loading the dough units into the oven.