I wouldn't be surprised if there wasn't more low-hanging fruit like this.

DateAndTime class>>#now is purposefully "slow" to assure DateAndTime
now < DateAndTime now.  Dave, I'm not sure whether you preserved that
behavior, if not it might not be a very fair benchmark comparison..

On Mon, Jun 2, 2014 at 9:53 AM,  <commits at source.squeak.org> wrote:
> Chris Muller uploaded a new version of Kernel to project The Trunk:
> http://source.squeak.org/trunk/Kernel-cmm.855.mcz
>
> ==================== Summary ====================
>
> Name: Kernel-cmm.855
> Author: cmm
> Time: 2 June 2014, 9:53:24.175 am
> UUID: 478f3548-e587-4dd9-8962-d6ba6dbe2035
> Ancestors: Kernel-eem.854
>
> - A simple fix for an 8X performance improvement in DateAndTime>>#< as reported by LXTestDateAndTimePerformance.
>
> =============== Diff against Kernel-eem.854 ===============
>
> Item was changed:
>   ----- Method: DateAndTime>>< (in category 'ansi protocol') -----
> + < comparand
> - < comparand
>         "comparand conforms to protocol DateAndTime,
>         or can be converted into something that conforms."
> +       | lvalue rvalue comparandAsDateAndTime |
> -       | lticks rticks comparandAsDateAndTime |
>         comparandAsDateAndTime := comparand asDateAndTime.
>         offset = comparandAsDateAndTime offset
> +               ifTrue:
> +                       [ lvalue := self.
> +                       rvalue := comparandAsDateAndTime ]
> +               ifFalse:
> +                       [ lvalue := self asUTC.
> +                       rvalue := comparandAsDateAndTime asUTC ].
> +       ^ lvalue julianDayNumber < rvalue julianDayNumber or:
> +               [ lvalue julianDayNumber > rvalue julianDayNumber
> +                       ifTrue: [ false ]
> +                       ifFalse:
> +                               [ lvalue secondsSinceMidnight < rvalue secondsSinceMidnight or:
> +                                       [ lvalue secondsSinceMidnight > rvalue secondsSinceMidnight
> +                                               ifTrue: [ false ]
> +                                               ifFalse: [ lvalue nanoSecond < rvalue nanoSecond ] ] ] ]!
> -               ifTrue: [lticks := self ticks.
> -                       rticks := comparandAsDateAndTime ticks]
> -               ifFalse: [lticks := self asUTC ticks.
> -                       rticks := comparandAsDateAndTime asUTC ticks].
> -       ^ lticks first < rticks first
> -               or: [lticks first > rticks first
> -                               ifTrue: [false]
> -                               ifFalse: [lticks second < rticks second
> -                                               or: [lticks second > rticks second
> -                                                               ifTrue: [false]
> -                                                               ifFalse: [lticks third < rticks third]]]]
> - !
>
> Item was changed:
>   ----- Method: DateAndTime>>= (in category 'ansi protocol') -----
>   = aDateAndTimeOrTimeStamp
>         self == aDateAndTimeOrTimeStamp ifTrue: [ ^ true ].
>         ((aDateAndTimeOrTimeStamp isKindOf: self class)
>                 or: [aDateAndTimeOrTimeStamp isKindOf: DateAndTime orOf: TimeStamp])
>                         ifFalse: [ ^ false ].
>         ^ self offset = aDateAndTimeOrTimeStamp offset
>                 ifTrue: [ self hasEqualTicks: aDateAndTimeOrTimeStamp ]
> +               ifFalse: [ self asUTC hasEqualTicks: aDateAndTimeOrTimeStamp asUTC ]!
> -               ifFalse: [ self asUTC ticks = aDateAndTimeOrTimeStamp asUTC ticks ]!
>
>