Rhythm notation

[Serial_Apologist]

Ok, I’ll bite: please explain 5/5: just what is the note value of which you’re counting 5 in a bar.

It wold have to be a dotted crotchet, surely? But I know of no such time signature.

[Joseph K]

Ok, I’ll bite: please explain 5/5: just what is the note value of which you’re counting 5 in a bar.

It would be five fifths-of-a-semibreve. So it would have the same duration as a 4/4 bar, except you'd count it as quintuplets.

Some composers like Ferneyhough have made use of such 'irrational' time signatures.

[Eine Alpensinfonie]

A composer/arranger generally wants his/her music to be performed as widely as possible, which means it makes sense to make the notation to be as simple to read as possible.
My pet hate is vocal music that don't used instrumental beaming, replacing it with groupings that follow word syllables. It makes accurate reading of rhythms more difficult for singers. Fortunately, most publishers have abandoned this practice.

[Richard Barrett]

What makes it 8/8? Presumably the same would be true of 3+2+3 or 3+3+2 bars.

Amazing, Holmes! And the 3+2+3 etc. may be specified by the composer to make it clearer where necessary.

It isn't a question of being trapped by convention but of using a language (music notation) in such a way as to communicate in a clear and comprehensible way to the intended recipients. If I decide to use the word "walnut" to mean "teacup" you're going to be wondering why.