Why is Lindsey on Behind the Mask and Time?

[Fleetwood Jack]

Howdy! It's great to be back. I haven't posted in awhile on here with school and work and all that jazz. But, I've had a question burning inside of me for the past five minutes, and I need my fellow Ledgies opinions. What's the reason Lindsey's on the title track of Behind the Mask and Nothing Without You from Time? Was he required to at least appear in one way or another or did the band just have a decent working relationship back then that didn't allow them to permanently cut each other off? This is a question I've been pondering, especially considering recent events.