Your analysis is a bit confusing. You change your base from AB to games, then from 'ABs available for HRs' to 'HRs per month'. As a friendly word of advice, keep it consistent throughout and keep your base something that can't vary- like ABs. ABs can vary in a game, and per month. Additionlly, it looks like you try to back your argument quantitatively, but really its a qualitative argument. You just don't think Gomes will keep it up. I agree, he's not going to hit 60. But I like his chances for 40, and I doubt I'll get a sure-fire 40 HR guy for him at this point.
Now let me try to follow your research and add something qualitatively:
HR/AB in 2005: 16.6
HR/AB in 2006: 6.7
Accounting for strikeouts (how many HR every time he gets wood on the ball):
HR/(AB-K) in 2005: 11.2
HR/(AB-K) in 2006: 4.0
Let's just say that the rest of the year, he returns to hit HRs at the rate he did in 2005. I think it's fair to assume he's better this year, but let's use last year's rate anyway. I'll use your projection of 543 ABs for 2006, and he already has 67, so 543-67=476.
467 / x = 16.6
x = 28.1 HR the rest of the way, giving him 38 HR this year if he returns to the HR rate he had last year.
Now lets again account for Ks. We'll use Gomes' 2006 K rate (he has Ked 40.3% of his ABs this year) and his 2005 HR rate:
[467 * (1-.403)] / x = 11.2
So even if Gomes returns to hitting HRs at the rate he did in 2005 while STILL striking out at the rate he has in 2006, he'll hit 25 more the rest of the way, giving him 35 HR this year. Barring injury, I'd have to consider this a floor on him this year in the HR department. I see adjusting this to 40-45 based on added MLB experience.