Questions about Marmalade to my Beer

It came to me this morning, while preparing toast.
I plan to brew a Mild, British style pale ale, brewed with Orange Marmalade.

I have no recipe yet. based on what i have read thus far, i will likely design a standard british mild pale ale, But then tweak it by eliminating all flavoring and aroma hops, and reducing the IBUs by about 10%. This should give a good base beer that will compliment the fruit flavor.

Now, about that marmalade. The only information I found on this was a post by another homebrewer, on a seperate forum. He did it with an english bitter, and added 2 lbs of marmalade with 5 minutes remaining in the boil. His final results: the orange was only present as a subtle after taste. He was hoping for a bigger orange presence. I have a few questions or thoughts on this.....

Much of the flavor may have been lost in the boil?
Additional Flavor loss during primary fermentation (similar to hop aroma loss when dryhopping in the primary)?
One response to his brew was that the High amount of pectin in marmalade could POSSIBLY ferment into methanol. Is this likely/possible? And is it MORE likely to happen if i were to add mine during the secondary fermentation instead?

My initial plan, subject to change based on feedback:
I will add it to the secondary.
I will sanitize 2 lbs of marmalade by placing it in a cup or so of water, and hold it for 1/2 hr at 150 degrees (hoping the lower temp will avoid pectin haze). I will pour the result into the secondary, and rack the beer onto it.
The secondary will be a bucket not a carboy. I have read that fruit may cause a very vigorous secondary fermentation, and that a carboy is ill advised.

I appreciate any and all feedback. Thanks!

Never used it in beer, but if I did I'd consider going with Oranges, Lemons and sugar. I wouldn't want any preservatives nor the expense of buying a purely natural version. Agree that in the boil you are going to lose most of the flavors.

Thanks Sam.
The more I think about it, the more I see your point. I would be better served using the ingredients for marmalade, rather than the finished, shelf-stable product. This also enables me to have only the natural amount of pectin found in citrus.
Now, as a follow up, should i even bother with Sugar? I can do the lemon, Oranges. But wouldn't the sugar have no other impact that to create a higher alcohol level/flavor, similar to adding sugar to a standard brew?
Also, thoughts on adding orange peel as well? It's used in marmalade, but would it cause some kind of harsh bitterness to the beer?

Yeah, you don't really need the sugar. Orange peel is a pretty popular addition, most LHBS usually have a few choices. Lots of recipes detail using the oranges and the peels so I would look at some of them for clues on how to use them.