Stackpole was an EXTREMELY productive writer back then. In his prime, he could churn out 3-5 books per year, in addition to the other shit he was doing. IIRC, he banged out Assumption of Risk in less than a month.
I remember that he wrote a number of postings on why he quit BattleTech. It had a lot to do with FASA's constant cash flow problems and the resulting irregularities with the royalty payments, which were pretty meager to begin with. I remember something about FASA jewing him out of tens of thousands of Dorrar in royalties for foreign language sales. What finally broke the camel's back was FASA trying to cut back his royalties to an even lower level at a time when he was actually doing pretty well with his own stuff and his Star Wars novels.
Another problem was ROC Books, the publisher of the BT novels. They were constantly cutting back on the word allowance per novel to bring down printing costs, down to 80.000 words at the end. Most Stackpole's BT novels were 100+k words. Stackpole found that this artificial contraint impacted his ability to produce a decent novel. It also became clear that ROC didn't really give a shit about the BT novels anymore. In addition to the novels getting shorter, they even let some of the spine novels go out of print right around the time when they were doing a new edition of the Warrior Trilogy - which was downright moronic. Also, the cover artwork became progressively shittier.