PIE *h1eish2-: 'mad attack'?

Dear List,

I have a query relating to the PIE root *h1eish2- (as given in
Mayrhofer's EWAia; in Pokorny it is *eis-1) 'to send (move rapidly,
set in motion)'. This root appears in several IE words
denoting furious passion:

Avestan ae:s^ma- (from the suffixed IE form *eis-mo-) 'anger'

Old Indo-Aryan is.min (from the suffixed IE form *eis-mo-
) 'impetuous' (= furious), an adjective appearing four times in the
RV to characterize the wild and impetuous entry of the storm-gods
Maruts and of their father Rudra

Latin i:ra-, having a more archaic form (attested in Plautus) eira-
(from the suffixed IE form *eis-a:-) 'anger, rage'

Greek oima- (from the suffixed IE form with o-grade ablaut *ois-ma-
) 'stormy attack, rush, instigation', oistros- (from the suffixed IE
form with o-grade ablaut *ois-tro-) 'madness'

Old Norse eisa- (from the IE form with o-grade ablaut *ois-) 'to
storm in'

According to G. Dumézil (quoted in M. Speidel, "Berserks: A History
of Indo-European 'Mad Warriors'", _Journal of World History_ 13,
[2002], pp. 277-8), Pokorny's PIE root *eis-1 would constitute "a
technical term of the Indo-European 'warrior bands' [who fought
madly and wildly, and were 'specialized' in going berserk]", i.e., a
term originally designating a mad attack, and only in a wider
sense 'to send, move rapidly, set in motion'.

Is this thesis plausible?

Best,
Francesco