This will be a (rare) long one for me.
My H had his affair in the mid 90's.
I worked things out without any message board to bounce ideas off of.
Hence, I made mistakes that might have been preventable.
But, guess what? I don't regret my mistakes, I learned powerful lessons from mistakes.
Then, I found an infidelity forum and joined, as Pepperband.

It was way different from this forum.
"Every Woman's Village" later it became "Redbook" (the magazine)
Equally represented were BW & BH , WW & WH, OW & OM.
There was no prevailing "point of view" on that forum.
There were no plans for recovery.
Pretty much, it was a free-for-all.
I learned a LOT about how waywards think, and also a lot about how TOW and TOM think.
I was able to hold my own on that forum - and I learned how to post logically in response to the illogical.

I also learned when to take a step back and cut my losses.
Then, there was an incident on that board. It became more difficult to post because we learned that 2 of the moderators were "seeing" each other romantically.

They were in an affair.
We (on that other, earlier forum) were aware of the MB forums. We even read them from time to time.
We had no understanding and even less regard for what we saw as a stupid choice ... which was "Plan A".
However, there was an exodus of members who flocked to MB all at once when we discovered we were being moderated by infidels.

We had a name for ourselves ... "Redbook Riff-Raff".

Soooooooooo, when I arrived on MB I was already YEARS into recovery, but had very little knowledge and little respect for Harley's methods. But at least this board was not infidel-run.

I read a lot of posts written by the old-timers who preceded my arrival. I read the site info. I read Harley books.
I also read
Passionate Marriage by Schnarch.
All at once I got insight into Plan A. I could embrace plan A. I could think of Plan A in a light other than "give the infidel goodies they don't deserve".
SSS - I recommend you give Schnarch's book a go - when you're feeling ambitious. It's a difficult read, but you will get so much out of it. It appears on the surface to be about sex, but it's really about intimacy. Deep and abiding and spiritual intimacy !!!

Tell GM that if he reads that book and doesn't get valuable insight from it, I'll drink goat milk

(which I hate).
I had a lightbulb moment about Plan A when I read Schnarch ... and I wrote about it. (below)
Looking back ... I can see I worked myself through a very awkward "plan A" .... although I never heard of plan A until years into recovery and I started poking around this site. Looking back ... I can see my efforts to become differentiated ... although I did not read Schnarch's "Passionate Marriage " until years into recovery.
Plan A is very much complementary to Schnarch's ideas of differentiation. Developing a positive identity within the context of a marriage struggling to overcome infidelity. Developing a strong sense of self-worth that is valid both within and outside the boundaries of the marriage.
I can NOW see plan A as a path to greater self worth and NOT necessarily as a plan to "win back" the heart and mind of the infidel ... although that might happen. It is a plan to differentiate myself and identify myself as a worthy person apart from the circumstances of the marriage relationship. Plan A'ers are not like doormats to wipe your feet upon and to mis-use .... more like a *welcome home* sign... if both persons choose to re-inter the marriage! Plan A says : "I can hold onto my better self under the worst of circumstances".
Schnarch says: "We develop a contingent identity based on a 'self-in-relationship'. Because our identity depends on the relationship, we may demand that our partner doesn't change so that our identity won't either."
Then ... comes the grenade of infidelity tossed into the marriage and the entire fusion of identities is blown apart! The aftermath of the grenade then boils down to this question ....
WHO THE HECK AM I ... AND ... WHO THE HECK ARE YOU?
And, asking this question to the *fogged-in* infidel is pointless. They got INTO the affair because they were lost to themselves, and went searching for a new self .... and, INSTEAD of differentiating themselves ... they fused identity to yet another relationship ... actually moving away from a healthy differentiated view of their self-worth ----> I am wonderful because my affair partner thinks so.
Plan A says and demonstrates to OURSELVES: I am not some weak pathetic person deserving to be abandoned or cheated. I am demonstrating decent and loving behaviour. I am worthy of love and devotion. ... If the infidel notices .... double bonus points. If not, I become better differentiated along the way ... and I can see my strengths despite terrible and hurtful circumstances.
Once I become more fully differentiated and have stable and accurate self-worth (after the grenade) ... I am then in the position to identify
healthy choices. I can honestly say that I will be a sensational woman within this marriage... or after this marriage terminates.
I think I finally understand what I went through. I understand that I am the better woman for it. I understand my spouse is the better man for it.
That is a powerful message to myself. The anxiety that floods the betrayed spouse is the perceived loss of identity . Self worth and a differentiated identity is the harvest of plan A .
I think I get it now.
Best to all of you travelers on this journey!
I embrace Plan A (when it's done right) as a personal choice to grow bigger rather than smaller as a response to infidelity.
So - I became a fan of Plan Harley
after the fact 
Sometime after this, I wrote the carrot/stick post because I was tired of reading things like:
"I've been doing plan A. I have been nice to WS." It just made me NUTZ that Plan A was frequently interpreted as "plan nice"
Carrot/Stick is MY personal interpretation of Harley's plan A ... and it has not been validated or given a stamp of approval in any way by Harley, no matter how many times it gets quoted.
As you can tell - I often start "idea" or "theory" threads.
I get the most out of my time on MB this way.
I get challenged by other people's ideas. Which I like. I get a bigger picture of my own thinking process. I try to apply an underlying value first BEFORE offering advice.
I succeed, I fail, I fall, I get back up.
I try not to take things personally, and I usually succeed at that.
Sometimes I do get an emotional visceral reaction to either a situation or a particular personality, and I try to avoid posting until I've figured myself out first. But, I fail there at times too. But, guess what? I am quick to forgive myself

because I only have 25-30 years left to live (if God lets me) and I hate to waste precious time scolding myself.
Again, SSS and GM, I do recommend
Passionate Marriage for you both , some where along this journey. You'll hate me at first for recommending, but you'll get a lot out of it despite me or yourselves
Right after my own D-Day, a friend said to me:
"I think you will make it through this and one day you will be counseling others about infidelity."That pissed me off. But, she knew me too well. She was right. Helping others is the best way to heal ourselves. Especially if we are getting challenged by others along the way.
It's a pretty awesome forum!