Here's one reason not to put boilerplate allegations of agency -- e.g., "At all times relevant herein, Defendants, and each of them, acted as an agent of each other Defendant in connection with the acts and omissions alleged herein." -- into your complaint.
It may well come back to bite you.
Plaintiff would likely have been able to avoid arbitration if his lawyer had omitted that common pleading mantra. But he instead did what most other lawyers do. And, today, his client pays for it.
Word to the wise.