david lang wrote:
Thanks for the input chaps. No magic bullet then.......

Plan 'B'.

I'll try cutting a 6mm deep dado in the sides & screwing through from
the outside - hopefully the tight fit of the shelf in the dado will
stop the splitting.

Plan 'B' worked a treat! Applied glue to the dados (Titebond 11) and used
3.5 x 40 SPAX 'M' MDF screws from B&Q. No splitting on the trial run and
virtually no expansion on final assembly. Straight in no pilot holes at
all.

SPAX 'M' screws aren't cheap mind, £5:98 for 100 - but they do what they say
on the tin.

Joints are as tight & strong as they could be - jobs a good un!

Dave