Done implemented on branch window-scroll-alt.
Added tests from this branch side by side to those from the window-scroll branch #101

I'd appreciate if people could try the new tests on their available platforms and comment on the results.

I decided that if this alternative was to prevail, it should be 2.0.0 rather than 1.5.0 because it's even less backwards-compatible than the other option and it contains a highly requested and powerful feature.

Windows Phone 8.1:

These do not animate:
Max window scrolling, within an iframe (compat mode)
Max window scrolling, within an iframe (quirks mode)
Max iframe scrolling from outside (compat mode)
Max iframe scrolling from outside (quirks mode)

In the old version they did animate but not always, depending on when what was loaded.

Ok, I'm less concerned about the iframe cases honestly, they are rare. It could be due to a bad test implementation it's not top quality.
Do you know when did those iframe tests failed on the 1.5.0 version? I'd like to try and fix it if really a bug on the test.

It has to do with timing i guess. When i select the iframe and refresh only that the scrolling happens. Otherwise it's just puts the "agent information" instantly.

Same happens with 2.0.0 or that one never works at all?

In the 2.0.0 nothing happens on the iframe pages. The old 1.5 did only fire if i refresh the iframe myself.

Windows 7
Firefox 36.0.1 - ALL OK
Chrome 41.0.2272.76 - ALL OK
IE 10.0.9200.16750 - ALL OK

iPhone 4S
Chrome 40.0.2214.73 - ALL OK except iframes
Safari (not sure where's the version) - ALL OK except iframes

I think the iframes don't work just because the tests are not rendered correctly on these browsers, the iframe is full height without overflow. I did a few changes but still no luck, I don't worry much about it honestly.

Mac OSX Yosemite 10.10.1
Chrome 41.0.2272.89 - ALL OK
Safari 8.0 - ALL OK

I'd really like to release this as 2.0.0, was hoping more people could test it.
I might release it and if any issue arises fix it for 2.0.1.
Considering it's a major version bump complete backwards compatibility shouldn't be expected anyway.

I merged 2.0.0 to master via #109.
If you have any issue after the update, first check this link, If your problem is not solved then go ahead and report the issue.