Teams willing to consistently outspend the cap don't have a cliff. I highly doubt John Henry is willing to fill his holes with money on a permanent basis. Once Betts, Bogaerts, Bradley, Sale, Kimbrel, Pomeranz et al get expensive, I think DD will have to get creative because you wont be able to keep them all. That is where having a deep farm can save you. But DD dealt away the farm and now there is a noticeable gap in talent at the top. This is why you have a cliff. Henry prioritized the fans over development. Dave would have been better off riding it out for 16-17 and then going for it all in 18-19 when the FA market is better and with another big draft in the rear view mirror. Instead, he's got a 93 win team that is entering 2018 as banged up as ever with nearly no money coming off the books and no big prospects ready to step in. He has to fix the roster with money, and he is doing so a year or so before he has to. When he spends this offseason, it seals the fate of the cliff because there wont be any money left to lock up the true core of this team.
I also read one post here about how you can "rebuild with one big trade at the deadline". That is absolutely not true. Yes, the Yankees did really well at their 2016 deadline, but we graduated Sanchez, Bird, Severino, and Judge in that time and dealt for Frazier, Robertson, Kahnle, Gray and Garcia with guys who we either drafted/signed or dealt off other low level players for. We kept the big names obtained from the Miller, McCann, Chapman, and Beltran deals. We rebuilt with our own players and now we have a top farm with a mix of the guys we traded for and guys we drafted and developed and have a title contending team led by guys we drafted or signed. If you think the rebuild happened in one mid season, you are entirely incorrect