A few thoughts on simplifying the copula for learning. It seems that within dialect variation, one can get a system that is not dummed down, but is regualar. Just thought I'd put it out there.


Present/Future rules: present (root before consonant; root +b before vowel)

independent sentances (direct statements). Used in initial position (like VSO)

is	is múinteoir é
ní (is)	ní (is) múinteoir
an	an fíor sin?
nach	nach ea?

dependant sentances (reportage). Used in middle position

go	deir sé go maith an fear é		gob	deir sé gob é is cúis leat
nach	sílim nach fiú scilling é		nab	sílim nab é
an	deir sí "an bhfuil tú go deas?"
nach	deir síad nach bhfuil siad ann?		nab?

relative direct (predication) Used in middle position

is	an gasúr is fearr
nach	rud nach fíor		nab	rud nab ann

relative indirect (genitive relative) Used in middle position

a	an duine a leis é		ab	aon duine ab eol dó an freagra
nach	cailín nach cuimhin léi mé		nab	éan nab eitilt tharam

Past/Conditional rules: (root + r and lention of following word; before consonant, root +rbh and lenition; except for ba whicj prefixes to following b; ba places dh between it and disjunctive form of personal pronoun)

independent sentances (direct statements) Used in initial position

ba	ba múinteoir é		b'	b'éan é
níor	níor mhaith liom goil		níorbh	níorbh éan é
ar	ar mhaith leat X?		arbh	arbh fhearr leat fanacht?
nár	nár mhaith leat?		nárbh	nárbh fhearr leat imeacht?

dependant sentances (reportage) Used in middle position

gur	dúirt sé gur mór an náire é		gurbh	deir sé gob é is cúis leat
nár	shíl sé nár pheaca é		nárbh	sílim nárbh é
ar	d'fhriafraigh Pól de ar ghá sin?		arbh	ní rabh a fhios agat arbh fhíor é?
nár	shíl sí nár pheaca é?		nárbh	shíl sí nárbh fheidir a dheanamh?

relative direct (predication) Used in middle position

ba	an teach ba mhó		ab	an t-éan b'óige
nár	rud nár thuig sé		nárbh	rud nárbh eol sé

relative indirect (genitive relative) Used in middle position

ar	an duine ar leis an teach		arbh	na páistí arbh fhearr leo fanacht
nár	an duine nár leis an teach		nárbh	na páistí nárbh fhearr leo fanacht

The matrix:

is/ba
ní(h)(or)(bh)
a(n)(b)(r)(bh)
ná(ch)(r)(bh)
go(b)(r)(bh)
ná/na(ch)(r)(bh)

A Bhirn, I'll be honest and tell you that a lot of your posts come across as cryptic to me. As regards simplifying the copula for the purposes of learning, there are many simple guides out there already, none of which require a matrix. Here's a simple way of looking at it:

Present Tense:
Is peann é. Ní peann é. An peann é?
Is asal é. Ní asal é. An asal é?

Present Tense indirect speech:
...gur peann é ...nach peann é ..."an peann é?"
...gurb asal é ...nach asal é ..."an asal é?"

Past Tense:
Ba pheann é. Níor pheann é. Ar pheann é?
B'asal é. Níorbh asal é. Arbh asal é?

Present Tense indirect speech:
...gur pheann é ...nár pheann é ..."ar pheann é?"
...gurbh asal é ...nárbh asal é ..."arbh asal é?"

And of course there's different dialects, some of which say "go mba" instead of "gur".