Is Jenna Maroney ( 30 Rock) based on Amy Poehler and Tammy Swanson (Parks and Recreation) based on Tina Fey Bossypants?

I just finished reading 'Bossypants' by Tina Fey, her 'autobiography/not really an autobiography/blandly humourous commentary on disconnected parts of her life/excessively political and feminist agenda'. It was actually quite a good, easy read, and at no point was I bored. I did also laugh out loud 2 or 3 times. She does (accidentally maybe) paint a sort-of mean spirited cut-throat picture of herself as someone who sold her soul to be a success, and also interestingly the book leaves out any detail of how she met, dated and married her husband, and almost any detail about how she transitioned from working at a reception desk at a YMCA in Chicago to being head writer at Saturday Night Live, which leaves the reader feeling slightly suspcious about these events which are so conspicuously absent from the book. The picture which the mind forms of Tina Fey from her writing is one of a very clever and funny, but ruthless and ambitous-to-a-fault lady, who you would not put it past to have committed shenanigans in attaining both hubby and job...

This highly judgemental theory I have come to, also helps with my theory that somewhere along the line, Tina Fey and Amy Poehler fell out, and that they are now maliciously parodying one another on their respective hit shows. In 30 Rock, Jenna Maroney is a blonde co-star/co-worker with Liz Lemon (Fey). In the fictional world of 30 Rock, Lemon and Maroney came up through a Chicago Improv Group (as did Fey and Poehler), before both joining the team of TGS (SNL in real life), one as a blonde star (Maroney/Poehler), and one as the writer (Lemon/Fey). At first I thought maybe this was just a coincidence, until I got caught up on Poehler's 'Parks and Recreation', which (is great and) is written and produced by the same guys who made the US version of The Office. I noticed that the demented psiren Tammy Swanson (ex-wife of the almighty moustachioed Ron) looks very like (uncannily like) Tina Fey, and is a cut-throat manipulator who will literally use anyone or anything and do anything to anyone or anything to get her way.

So are Tammi Swanson and Jenna Maroney actually malicious mockeries of one another being batted back and forth like a tennis ball by Fey and Poehler?
Are they actually a bit of best-friends-banter between two enlightened feminists who are having a laugh with one another?
Or am I just reading a whole load of nonsense into something which isnt actually there?
Probably.