vivek ji , sure I know that but in certain combinations only.Charles shobhraj has guru chandala yoga and there are many exceptionally good people born in same year has same too.But guru with rahu doesnt always can harm , if they are in 6th house it wud be Guru adding grace to rahu s' potential to defeat enemy...it wud add scruples to rahus' demeanor.

Namaskaar SG ji,
Yes! in raashi chart the two will stay together for a few months and countless children will be born during the time. But here we are discussing Guru +Raahu and the effect it will have on a chart.
Imagine a Saatvik and Dharmic person stuck with a person having no Dharma or is the very anti thesis of what the Dharmic person stands for. Who enjoys the situation more?
I know i am speaking in a very Black or White manner but the gradation come because of other factors.
Superimpose the Kaalachakra on the Dig Chakra and you will see.
vivek.

Guru signifies warm and healthy wisdom.
Rahu signifies materiality and illusion.

Let us add the two in a conjunction, or a friendly dance. What happens?

Does the WARM and HEALTHY dance remain so at all, or get spoilt/polluted?

Again Rahu abnormally accentuates the qualities of a planet it is conjunct with.. leading to NOT normal results.

Rahu conjunct Venus abnormally accentuates Venusian qualities, leading to.....

Rahu conjunct Mercury abnormally accentuates the thinking qualities, leading to wayward thinking and intelligence giving wayward results.

Rahu conjunct Moon abnormally accentuates mental power, leading to too much mental power, not in proper balance with its results/proper use.

Rahu conjunct Mars abnormally accentuates the boldness of Mars, leading to too much unwise courage/recklessness.

Rahu conjunct Sun abnormally accentuates the  Ego qualities, and affects the father/relations with the father.

You tell us about its conjunction with Saturn?

Rahu Jupiter conjunction is termed Guru Chandala yoga which is not good/healthy.

RishiRahul

Thanks to both of you Rashirahul ji and Vivek ji.

Does its conjunction with Saturn accentuate meloncholic, selfish,  cold and unforgiving aspect of Shani Dev.

Hi Certain,

Wouldnt Saturn signify restriction here.. that is, to Jupiter's qualities.

RishiRahul