A shift in algo?

I have been used on seeing my internal pages scoring in SERPS for certain keywords. But lately, many searches brings the index page instead the low hierarchy pages, at approx. the same position. The pattern is as follow:
- the index contains the keyword in title (the title is long)
- the index contains the keyword once or twice in the page text
- the index is linked by the keyword from the lower hierarchy themed pages
- I can see this not frequently, but repeatedly, perhaps depending on datacenter
-if this happens, it happens for most of the targeted keywords at once

Did anybody noticed something similar? Is this a shift towards site theming and G simply chooses the top page of the themed site (for the several themes I have)?

Looking at your answers.

 

Please clarify your explination - it's hard to be clear on what you are doing.

 

Especially this one...

As I read it now, it is just very bad practice.

 

I've noticed the same thing for new index pages I've created, not for old index pages.

 

What thing? This whole thread is like reading something in a foreign language. Other than the quoted phrase, the only thing I think I understand is

and even that has a spelling mistake and a confusing ending.

 

OK I am sorry. The faster I am typing, the more miserable the English. You may have guessed that E. is not my native language. On the other hand, minstrel as a psychologist should do better job in interpreting incomprehensible text .

Once again. I have a local language website. Since it is webdesign and SEO oriented, all terms are moderately competitive. I have therefore optimised internal pages of the site for individual terms. It worked OK for a year or so, but recently these pages were replaced by the index in Google SERPS for most of the keywords. When searching for an individual keyword, sometimes two internal pages comes out, sometimes the index followed by an internal page.

I have been asking:

Did anybody noticed something similar?

Does this indicate possible shift towards site theming (parts of the site are themed for individual keywords and linked to the index) and/or more weight on internal IBLs?

A claim without any proof is just this - a claim.

 

It is just a claim indeed, based on incomprehensable text.

I still don't know what you mean. This is my interpretation:

The index is linked (to or from?) by the keyword (by links with the main targeted keyword in the anchor text?) from the lower hierarchy (in deeper folders? Or just lower in a schematic tree starting from the index?) themed pages (what do you mean, themed? Themed as in related to the index? Themed as in related to the anchor text?).

English isn't my #1 language either, it might be just that...

 

I am using a very shallow(http://www.searchengineworld.com/engine/theme_pyramids.htm) pyramid structure, the second and third hierarchy pages are themed and use their primary keyword to link up to the index.

But back to the topic. Anybody noticed similar shift in SERPS?