«Arsenal has been financially constrained over the years because of the club’s move to the new stadium».
Is it a myth?
No.

Last Deloitte’s “Annual Review of Football Finance” shows following figures spent by clubs:

(breakdown by year can be found here. )

Deloitte is not talking about “money available”, it is talking about “money spent”.
Could you spend unavailable money?

During this 5 year period the clubs won:

ManUtd — 9 titles (EPL 06/07, 07/08 и 08/09, CL 07/08, LCup 05/06 и 08/09, Community Shields 07, 08, World Club Champiomship 08)

Chelsea — 7 titles(EPL 04/05 и 05/06, FA Cup 06/07 и 08/09, LCup 04/05 и 06/07, Community Shields 05)

Арсенал — 1 title (FA Cup 06/07 04/05)

Liverpool — 4 titles (FA Cup 06/07 05/06, Community Shields 06, ЛЧ 05, European Super Cup 05)

Tottenham — 1 title (LCup 08)

So the one title cost in round figures is:

ManUtd 58 mln.

Liverpool 138 mln.

Chelsea 143 mln.

Tottenham 312 mln.

Arsenal 480 mln.

This is sport efficiency of the leading English clubs.
The most efficient manager is SAF, the worst – AW.
At that ManUtd spent only 8,5% more than Arsenal.

Therefore the notion
«Arsenal has been financially constrained over the years because of the club’s move to the new stadium» is not a myth.
It is a falsehood.
Produced by Arsene Wenger in excuse of own lack of sport efficiency.

(also published at http://www.onlinegooner.com/exclusive/index.php?id=1768 )