Soka Gakkai scolars state "fact" when no fact exists

'Since karma is an essential property of every sentient individual, there is no trace in the Buddha’s teaching of such a thing as “collective karma”. This fact has profound moral implications.' -- Richard Gombrich expert on the Pali Canon of Buddhism and contributor to the SGI Institute of Oriental Philosophy [ http://www.iop.or.jp/Documents/1424/Gombrich.pdf ]

Of course there is collective karma. It is teaching in the Sutras [especially the Lotus Sutra] and it is an observable reality. 

"When he had spoken these words, there were some five thousand monks, nuns, laymen, and laywomen in the assembly who immediately rose from their seats, bowed to the Buddha, and withdrew. What was the reason for this? These persons had roots of guilt that were deep and manifold, and in addition they were overbearingly arrogant. What they had not attained they supposed they had attained, what they had not understood they supposed they had understood. And because they had this failing, they did not remain where they were.

The world-honored one was silent and did not try to detain them.

At this time the Buddha said to Shariputra, “Now this assembly of mine is free of branches and leaves, made up solely of the steadfast and truthful. Shariputra, it is well that these persons of overbearing arrogance have withdrawn. Now listen carefully and I will preach for you.” -- LS Ch. 2

And the four kinds of believers

who adhered to the doctrines then,

who heard Never Disparaging say,

“You will become buddhas!”

and through the causes thus created

encountered numberless buddhas—

they are here in this assembly,

a group of five hundred bodhisattvas,

and the four kinds of believers,

p.313men and women of pure faith

who now in my presence

listen to the Law.

In previous existences

I encouraged these persons

to listen to and accept this sutra,

the foremost in all the teachings,

unfolding it, teaching people,

and causing them to dwell in nirvana.

So in age after age they accepted and upheld

scriptures of this kind.

A million million ten thousand kalpas,

an inconceivable time will pass

before at last one can hear

this Lotus Sutra.

A million million ten thousand kalpas,

an inconceivable time will pass

before the buddhas, world-honored ones,

preach this sutra.

Therefore its practitioners,

after the Buddha has entered extinction,

when they hear a sutra like this

should entertain no doubts or perplexities

but should with a single mind

preach this sutra far and wide,

age after age encountering buddhas

and quickly completing the buddha way." - LS Ch. 20

Examples of collective karma are those with cerebral palsy, those born white, those killed in the holocaust, doctors, lawyers, indian chiefs. Either there is individual and group responsibility or there is none. Weal and woe either happens by chance, the will of god, or through the thoughts, words, and actions of individuals and groups. Those who have faith in the Lotus Sutra believe in personal and group responsibility caused by the thoughts, words, and deeds of individuals and groups accumulated since the infinite past. Who is the agent of your weal or woe? I hit my thumb with a hammer. I would be a fool to blame someone else. Likewise, only fools blame God, others, the environment, or chance for their fortune or misfortune.

"Question: If I have doubts, it is because I am an ignorant person. But if I doubt the words spoken to me by all persons of wisdom, then I will end up with nothing to believe in, and will merely live my life in vain, will I not?

Answer: In his dying instructions, the Buddha said, “Rely on the Law and not upon persons.” This means that if what a person says is not in agreement with what is expounded in the sutras, one should not believe it, no matter how fine the person may be...."