This part of your suggestion I like and is def not spoilish. It is just a counter showing how many techs you have acquired via trade. It will not be 100% accurate re WFYABTA as it will be total techs and not techs that affect an AIs counter.
That said, how do you increment this counter? I don't think there is an event re 'tech acquired thru trade'. DUH!
While it isn't spoiler information, it might be pretty confusing for those that don't exactly know how the counter works. Many players don't even know what the WFYABTA message means. It's pretty weird that the counter for traded technologies can be higher than the maximum level and you can still trade.
For instance: We have a civilisation that has a maximum WFYABTA counter of 10 at the difficulty level that we're playing at (the maximum value at which players are willing to trade is difficulty level dependent).
So we start trading technologies with several players and the WFYABTA counter goes up: 1,2,3,4,5,6 (after trading for 6 technologies) and at that point it goes down one time unknown to the player to 5. It starts going up again: 6,7,8 (after trading for another 3 technologies) and then again it goes down one time unknown to the player to 7. Then it goes up again to 8 after another trade. However, the counter that was programmed to count the number of traded technologies should now be at 10, since it should not show the 2 downward shifts. But we can still trade, so the actual counter is below 10 and the player knows this and he can record this on a piece of paper if he's willing to do so. He doesn't know, it is actually 8, but he knows it is below 10. After trading for another technology, the counter programmed to count the number of traded technologies will be at 11, but we can still trade, so we know the actual counter is below 10. It's actually at 9, but the player doesn't know this.
You could improve the counter that simply counts the number of traded technologies to do the following:
If counter >= max level counter and we can still trade, then set counter at max level -1.
But you need a counter for each civilisation, because each civilisation has a random chance that its counter will go down by 1 (if I understood the mechanism correctly).
In this case, the counter would show the possible maximum level of the WFYABTA counter as far as the player knows. The actual level of the counter could be lower than the shown number, but it can't be higher.
That made my night! Thatnks for helping alleviate much of the frustration cIV dealt me the past weekend. 
Anyway, I thought this was already put in, or I would have said something LONG ago.
