Apparently you are not able to understand the root of the problem which is length of these deals and that these deals all go well beyond the player’s prime. The teams hoped they would not pay for several years of just above replacement level but that is rarely the case. Stanton's deal is 5-8 years longer than all of these deals with the exception of ARod.Therefore, even though he was younger when he signed it, he will still be well past his prime for several years.Your focus on the fact he was younger when he signed the deal completely ignores the failure points associated with these deals.Perhaps more simply you have ignored the realities of the additional length of the deal.
You have also ignored that all of these players had equivalent WAR and most of them had higher WARs when they were signed.So, you are simply ignoring the potential for failure because it does not suite your argument.You are also ignoring how damaging it would be for a team with the Twins revenue to have a dead contract of this size if he fails.If that's not enough, you are also ignoring there will be better players next year that won't cost us top prospects.
No, I understand perfectly. You will make a case against signing or trading for any free agent (almost always 30+) or trading for any veteran player.
The key here is to get a player on a long contract that includes his age 28-32 seasons (your selection of players back this up) since that will likely give you substantial excess value. Even if you consider Stanton only to be a 5+ WAR/yr player then he is worth 40+M/yr. I think he definitely has 3-4 seasons of 5+ WAR left and that is why I choose this deal.
I find it convenient that you left out Miguel Cabrera's 2008 contract. Mauer's 2009 and ARod's 2008 contract were included.
For some reason you consider Ryan Howard and Ellsbury comparable which they are not even remotely close to. Howard average 1.3WAR for the two seasons before signing his ridiculous contract. Ellsbury's value was based on his defensive. I wouldn't even consider using Hamilton as an argument against signing any kind of FA due to his past.
Let's throw out those 3 comparisons out and you are left with
Tex - the early part of his contract has justified the later part even if he sucks now
Mauer - he was great until he suffered a concussion and even then his contract has not prevented the Twins from signing anyone or retaining anyone. It is not the reason that the Twins were bad for so long.
Pujols - He signed his contract at age 32. Your data certainly suggests that this is a bad idea. Getting Stanton at age 28 to enjoy the 4 peak years before Pujols signed his contract is a great idea. Signing Stanton after he could opt out is a poor idea.
Cabrera - fantastic deal (2008) despite many people at the time expecting it to be awful long term. Stanton isn't quite MCab but this is the upside of the deal. MCab's new contract = LOL
ARod - fantastic deal
Analyzing this the exact same way as you but getting rid of players that either sucked (Howard), had disproportionate defensive WAR (Ellsbury) or were recovering drug addicts (Hamilton) shows that this could be a huge win for the team that acquires him. I am not even sure that I would include a catcher as a comparable due to the wear and tear and increased chance of an injury. FWIW - I don't even regret Mauer's deal. It hasn't prevented the Twins from signing or retaining players.
The absolutely most important part of making this deal is finding players that will be at or near their peak for the time that the Twins have their young core under guaranteed team control. And increasing payroll substantially to add pitching. It certainly doesn't make any sense to add Stanton if you are rolling out last year's staff.
If a team has a chance to acquire an elite player that is 28 yrs old then they have to jump at that chance because they aren't available often.