[the bindlestiff]

Originally, engineers would respond immediately and fight whenever the opportunity provided itself. They would forget to accomplish their engineering tasks as a result and many dynamiting objectives would go unfinished. So Mal changed it so that they would be more focused on completing their goals.

Here's Mal' reasoning in his words:
Was playing some Fritz ET in a LAN party tonight, and one thing reallybothered me: the bots weren't as good about staying focused on their goals as much as the humans were. They're too eager to get into a fight sometimes, and it makes it difficult for them to capture/plant on objssometimes. So, I'm testing some changes to their goal priorities, as far as itconcerns enemies (and possible enemies). Engs should be more focused on planting, and all bots should be more focused on stealing/delivering objs.

Perhaps that is what you are observing. My problem is the opposite -- I get so involved in trying to finish the objective that I take damage and forget to defend myself!