What exactly needs to be safeguarded anyway?

I assume that if a four track main line is good enough for Crossrail
between Paddington and Maidenhead, then the continuation of the same
four track main line is good enough between Maidenhead and Reading. So
no additional land neeeding to be safeguarded?

As to clearances for knitting. Aren't all new structures built above
railway lines supposed to allow for a hypothetical future
electrification anyway? And whether that electrification is being done
for Crossrail or as a part of a more extensive GWML electrification
shouldn't surely make any difference to the physical clearances
needing to safeguarded above the line.

Possibly Crossrail might need additional platform capacity or
arrangements at Reading. But surely the Reading remodeling is being
projected with that in mind anyway?